2019 Petit Le Mans: The Live Blog

IMSA's season ends with a ten hour classic. Titles are at stake.

Motul Petit Le Mans at Road Atlanta
Brian ClearyGetty Images

Hour 10:00: The #33 Mercedes runs out of fuel after effectively defending his position for so long. Bill Auberlin is suddenly defending, instead, from the #29 Monteplast by Land Audi of Christopher Mies, but he successfully holds the spot, and the #33 Turner Motorsports BMW M6 wins one hell of a GTD race.

Your overall winner is the #31 Cadillac of Action Express Racing, ahead of the #10 Wayne Taylor Racing Cadillac and #7 Team Penske Acura. The #6 Acura, which finished today's race in fourth, takes the DPi title, meaning driver's championships for full season entrants Dane Cameron and Juan Pablo Montoya. A mistake in traffic that left a GTLM car spun could cause problems for the #10 Cadillac, however, which could promote the championship-winning Acura to the podium post-race.

The #62 Risi Competizione Ferrari takes the GTLM win, ahead of the #67 Ford GT and the #25 BMW M8 GTE. Porsche #912, which was hit from behind by the #10 Cadillac DPi on the second to last lap, clinches that class championship for drivers Laurens Vanthoor and Earl Bamber.

The #33 Turner Motorsport BMW wins in a GTD that had been a thrill from start to finish, allowing longtime BMW driver Bill Auberlin to tie Scott Pruett for most class wins in IMSA-sanctioned sports car racing history. The #29 Monteplast by Land Audi and #9 Pfaff Motorsport Porsche fill out that class podium, while the non-finishing #86 Meyer Shank Racing Acura NSX clinched the class championship earlier today.

The IMSA season begins anew in just over three months with the Rolex 24 at Daytona.

Hour 10:00: White flag.

Hour 9:58: #96 BMW driver Bill Auberlin finally attempts a move into turn 10, but #33 Mercedes driver Felipe Fraga defends well, and the lead remains. Two laps left for that class.

Hour 9:52: With gaps in DPi and GTLM growing to over two seconds, the battle to watch is, at least as they run, the all-out war for the win in GTD.

Hour 9:46: The top three in GTD are covered by less than the gap from first to second in GTLM, and the gap from first to second in GTLM is less than two seconds. The running order continues to be how they restarted, with the #67 Ford GT pushing the #62 Ferrari in GTLM, while the #33 Mercedes, with all of its fuel mileage concerns, leads the #96 BMW and #29 Audi in GTD.

Hour 9:41: The issue for Cadillac #5 is a brake rotor that appears to have shattered. With so little time left, that's probably race over for that car.

Hour 9:40: The overall leader, the #5 Cadillac, goes off into turn 10. That car seems to have an issue and will actually stop from what was just ten seconds ago the overall lead.

Catastrophic issues for the cars that restarted first and third have left the Cadillac #31 isuddenly in complete control of DPi yet again.

Hour 9:38: Timing and scoring suddenly shows that the #77 Mazda has lost a full ten seconds over the last lap. According to Mazda, the car is misfiring. A catastrophic ending for what just thirty minutes ago looked like a win waiting to happen.

The GT classes are running as they restarted, but their battles for their respective leads are now creating traffic for one another, which is creating a bit of a hornet's nest.

Hour 9:36: An awful start for the #77 Mazda, the car that likely would have won the race without that caution. It instead falls to fifth, and, with the pace it's shown since the sun set, likely cannot hope for much more than a third place finish.

Hour 9:35: Back to green. The battles for DPi and GTLM are now honest, with no gaps or fuel mileage situations to consider, and only the leader in GTD has any real concern about finishing the race without stopping again.

Hour 9:30, Full Course Caution 3: The #77 needed a full complement of fuel, while the #5 and #31 did not, so the lead change takes place as the DPi leaders pit. Action Express Cadillac #5 will lead Action Express Cadillac #31 and Mazda Team Joest #77 to green, with Wayne Taylor Racing #10 close behind.

Hour 9:20, Full Course Caution 3: Well, there goes the neighborhood.

The full course caution is out to recover the #63 Scuderia Corsa Ferrari, which was beached in the turn 10 gravel after making contact in a battle for fifth in class. All of those numbers, all of those situations playing out, they're irrelevant now.

The #77, by my math, had this race won, but that nice 31 second cushion the Mazda had is now gone. The entire DPi field will stop for the final time, and when that happens, every car will be able to make the end of the race on fuel. The strategy is over, and all four contenders will have fuel to make the end of the race.

The GTD-leading #33 Mercedes may not be able to make the end of the race on fuel even after this yellow, but the #96 BMW behind it is suddenly in a much better place on its fuel mileage than it was ten minutes ago. The #29 Land Audi was in position to win the race, but now will have to pass one, maybe two, cars to take that class win.

This is not a major change in GTLM, at least, where every team was comfortably in their window to finish the race without stopping again already.

Hour 9:15: The #5 Cadillac stops on schedule, so we can now see that it has 31 seconds to cut on the Mazda, assuming that car will finish with just one more stop. Some of that will be done by the shortened length of the stop itself, but a large portion of it will need to be cut on track.

Hour 9:08: Cadillac #31 stops very early in an attempt to split its two necessary stops in half, which seems to be a hedge against the #77's fuel strategy by Action Express Racing. That car will have to push very, very hard to apply any more immediate pressure to the Mazda, which is a full 40 seconds further up the road right now, but this could more likely get the #31 past the #10, which is on the Mazda's strategy, for third.

Hour 9:02: Turner Motorsport pits their #96 BMW with 58 minutes remaining, which the team is worried will not be enough time. Surely, that eliminates the chances of the #33 Riley Motorsport Mercedes and #63 Scuderia Corse Ferrari, which stopped six minutes and four minutes earlier respectively, from finishing the race without needing a final splash of fuel.

On the other hand, the cap between the #29 Monteplast by Land Audi and #9 Pfaff Porsche is just two seconds, and both cars have yet to make their final stop, so assuming their mileage is relatively comparable to what the BMW is getting, both should have no real worries about ending the race without stopping again. No matter how you cut it, GTD is also fated for a great finish.

Hour 9:00: Are you ready for this?

Mazda #77 lost about 30 seconds from its five second lead to its 25 second defecit over the past two hours. During its most recent stint, it went long enough on fuel under green flag conditions to, if repeated twice more, make the end of the race on fuel.

Its gap on the other side, were it to make one less stop than the #5 Cadillac, is about a 45 second lead.

Assume 25 seconds more lost and 15 saved due to fueling time for the #5 Cadillac and you're looking at the Mazda leading, on what could be its final gasps of fuel, and under pressure from not one but two Action Express Cadillac DPis in an hour.

Hour 8:50: GTLM's entire field are somewhat jumbled on strategy, but all should be able to make the end of the race on no more or less than one more stop, meaning that fueling time will be the only major variable still in play for that field. Those final stops should happen shortly.

GTD, meanwhile, is a bit more of a mess. There, the #96 BMW is cutting it a little closer than that team might be hoping on mileage, and the #63 Ferrari and #33 Mercedes are on, essentially the same strategy. That could open the door for the #29 Monteplast by Land Audi and #9 Pfaff Porsche to run hard from second and third while the other three contenders have to worry about saving fuel (or even a strategy involving a final splash-and-go stop).

Hour 8:49: Two significant developments in DPi; First, the #31 is suddenly within sight of the #5 in what's currently looking like the main battle on track for the race win. Both cars need two more stops, but the #5 has about 10 more minutes of fuel than the #31, which means its final stop will be quicker.

Perhaps more interestingly, though it is less likely to play out directly on track, the #77 Mazda is suddenly on pace to finish this race with just one more stop after its next stop. That car stops after a 37 minute stint and has just 70 minutes left in the race. Oliver Jarvis gets in that car, and he will have about 50 seconds of gap to burn through, plus however much time the #5 might be able to save by short-pitting for its final stop.

This is quite the battle.

Hour 8:38: Felipe Nasr tells NBC that the #31 "Just [doesn't] have the pace" it did earlier in the race, thanks to some combination of track conditions and minor damage to the car's floor. This comes as the #5 Cadillac seems to have come into its own, having built a hefty gap on the #77 Mazda that had briefly been in complete control of this race about 90 minutes earlier.

Hour 8:28: With just an hour and a half left and a realization looming that there may not be any more full course yellows to come, teams are now planning for a scenario in which the race runs green to the end.

One such team is Action Express racing, who have just put Pipo Derani in the #31 for the race's final 90 minutes.

Hour 8:05: The lead in GTLM for the #62 is now up to eight seconds, a return to form for the #62 Risi Competione Ferrari that had started on pole in class.

Hour 7:45: After nearly an hour of trying, the #62 Risi Competizione Ferrari is through to the GTLM lead, thanks in no small part to driver Alessandro Pier Guidi, who patiently waited for an opportunity before using the traffic of that tight battle for second in GTD to finally cause enough of a disruption to make a move on the #67 Ford for position.

Hour 7:40: The most intense battle on track is for second in GTD, where three cars on completely different strategies are running together on track. The #33 Mercedes is the leader of that group, which is about three seconds behind the class leader but won't be together much longer because those cars are each about fifteen minutes away from each other on their strategies. The leading #96 Turner BMW and the #9 Pfaff Motorsports Porsche in fourth are the only two of the top four on the same strategy, while the #29 Monteplast by Land Audi being the contender with the biggest fuel advantage.

Hour 7:35: The #77 Mazda went particularly long on this last stint, and will come out of the pits with nearly ten minutes of fuel advantage on the #5 Action Express entry, leaving that car now essentially on the #31's strategy.

The net lead GTLM is still separated by just half a car-length, and even the #3 Corvette, which just stopped after leading for fifteen minutes on an alternate strategy, was only two seconds ahead those two cars on track before its stop. If nothing significant changes, any outcome in that class should result in a close race.

Hour 7:23: NBC cameras seem to have missed it as it happened, but the #5 Cadillac of Mike Conway and Action Express Racing has just passed the #77 Mazda of Tristan Nunez and Mazda Team Joest for the overall lead. An impressive stint for Mike Conway.

Hour 7:20: The gap for the overall lead is under two seconds. The gap in GTD, currently a battle between the #96 Turner Motorsport BMW M6 and the #29 Monteplast by Land Audi R8 is under one second.

Hour 7:08: The #31 Cadillac has made up a fairly large portion of its gap to the overall leader over the last cycle of stops. That car is still off-schedule, but it is just four seconds behind the race-leading #77 Mazda as they run.

Hour 6:58: The #96 Turner Motorsport BMW is through to the GTD lead. A change may come soon in GTLM, as well, where the #62 Risi Competizione Ferrari is now just three seconds after the #67 Ford GT.

Hour 6:45: Even with one old tire and three new ones, the #33 Mercedes AMG GT of Riley Motorsports is still your current leader in GTD. That car has about 30 minutes less fuel than the Montaplast by Land car in third, and fifteen minutes less than the Turner Motorsport BMW in second.

Hour 6:33: The sun is setting at Road Atlanta. Night racing up next.

Mazda #77's overall lead is down to just two seconds, but the gap from second to third is up to twenty.

Hour 6:25: Sometimes something will happen that is truly unprecedented, but not in either a good or bad way. You simply must look at it and say "Okay, so that's happening." Today, we get one such event, from the two-car LMP2 class:

Hour 6:20: The #31 Cadillac had a similar issue to the #33 Mercedes, being unable to change its right-front tire, during its last stop. That will have an immense effect on that car's potential speed over the course of the next stint.

Hour 6:15: The #10 Wayne Taylor Racing Cadillac spins after some light contact in the far corners of the circuit. Driver Renger van der Zande resumes without issue, but will have lost quite a bit of time in the battle for fifth on track.

Hour 6:12: The #62 Risi Competizione Ferrari is suddenly under hard pressure from the #25 BMW M8 GTE for second in GTLM. Those two cars have the #912 Porsche just behind them, in what has become a tight three-way battle for second in a class where the leader is 14 seconds ahead of the rest of the pack.

GT-related drama continues in GTD, where the #33 Mercedes is suddenly well behind after an issue removing that car's right-rear wheel during a routine tire change. The issue wasn't resolved, so the car is out 0n track with three new tires and one old one. It's a minor issue, but one that could easily derail that car's race in such a competitive class.

Hour 6:02: The #31 Cadillac has a small off on the backstretch while chasing the #6 Acura for third overall. Driver Pipo Derani escapes without any visible damage, but any off-track excursion at such a high speed has to be worrying.

Hour 6:00: The GTD class, which was the source of this race's excitement before the entire DPi field decided to converge near the lead at the same time, continues to be host to a fantastic battle. The #33 Riley Motorsports Mercedes has a 20 second lead over the #96 Turner Motorsports BMW, but has 15 minutes less fuel. The #63 Scuderia Corsa Ferrari is on the same strategy, and just a few car lengths behind the BMW.

Hour 5:50: Everyone has completed their stops in DPi, so here's the gap-and-fuel situation as they run in what's shaping out to be a very, very interesting DPi battle.

Mazda #77 has a pretty big advantage as it takes the lead on the primary strategy, eight full seconds thanks to the extra time the #5 Cadillac lost in traffic during the actual stop cycle. The #5 is on the same strategy, about four seconds ahead of the #6 Acura on track, particularly impressive since that car is about five minutes behind the leaders on fuel. A further two seconds back is the #31 of Pipo Derani, likely the favorite to win the race, but the bigger issue than the gap to the leaders for that car is its ten minute mis-alignment on fuel load. That car will be pitting from behind for a large portion of the rest of the race, and will no longer gain an undercut advantage from it. In fact, even if the rest of the field decides to shorten their stints, they'll still gain an undercut advantage on that car while doing so.

The #7 Acura and #10 and #84 Cadillacs are still in contention, but do not belong in the immediate conversation with the top four as they run right now.

Hour 5:39: Eric Curran is now ceding the #31 Cadillac back to Pipo Derani, who will have a very real chance of retaking the lead by the end of this stint. Curran's mandatory drive time is complete, and that car should pretty quickly cycle back into the top four. Unfortunately for that team, though, the timing of Curran's mandatory drive time completion has left that car even more aggressively short-pitted than the leading #6 Acura, meaning that the car will be close to ten minutes off strategy again, just an hour after sacrificing a sizable fuel advantage to join the primary strategy before the most recent safety car.

Hour 5:30: The #3 Corvette, which stopped about 25 minutes ago, is about to cycle into the lead in GTLM. That car's now in the same situation that the #911 Porsche was during the last stint, running a half-cycle behind but leading because of its time on a clean track and fresh tires. For those keeping score at home, the #25 BMW M8 GTE was the last GTLM car to pit on the primary cycle, so they'll have nearly half an hour of a fuel advantage on that Corvette.

Hour 5:28: Meyer Shank Racing third driver Justin Marks on what happened to that team's #86 Acura NSX, which was previously running top six in GTD:

Hour 5:21: The #6 Acura of Simon Pagenaud, the championship leading car, is leading the race after a five-ish lap undercut of the rest of the field. That car's small lead means that cars from three different manufacturers are now within four seconds of the overall lead.

Hour 5:17: The entire DPi field is back on the same strategy, which means that the entire field has stopped over the course of the last two laps.

Hour 5:10: Nearly half an hour after the restart, the #77 Mazda is still within a car length of the overall lead and still trying to make a move to get that spot. Cadillac driver Joao Barbosa gets a little bit of a block from the lapped #54 CORE Autosport Nissan DPi, and Timo Bernhard is quickly able to get the Mazda into the lead. Unfortunately for Bernhard and Mazda Team Joest, the #5 is now applying a similar pressure to get that spot back.

Hour 5:06: The #52 PR1 Mathiasen LMP2 car is going behind the wall. There are no longer any running LMP2 cars left on track.

Hour 5:05: The race is officially past the halfway mark. We're a couple of hours away from losing daylight.

Hour 4:55: Meyer Shank Racing's #86 Acura NSX is billowing what appears to be blue smoke out of its left-rear corner. That car is slowing, but not stopping, with what looks like a potentially catastrophic issue. The car safely makes its way to the pit lane, but it's a very bad sign for a car that was previously running fourth in class.

Hour 4:52: If you're wondering why the top two are pulling away, it's because Eric Curran is now behind the wheel of the #52 Action Express Cadillac. Curran is good at what he does, but he's no longer a full time professional racing driver.

Curran drops to fourth after being passed by potential (and expected) DPi champion Dane Cameron in the #6 Acura. Graham Rahal, in the #7 Acura, is now pressuring him for fourth.

Hour 4:45: Back to green. Mazda #77 is the car to watch here, as it sits between the leading #5 Action Express Cadillac and its teammate, the fastest car on track, in third.

Hour 4:38, Full Course Caution 3: Our four cars attemptingaggressive off-cycle strategies, something one of the four had actually begun to abandon just before the safety car came out, are now normalized onto the primary strategy, so we can see where they've landed in what is essentially another complete reset for the healthy cars left on track: Cadillac #31 has fallen to third in DPi, after leading before the rest of the class hung them out to dry by switching strategies. Porsche #911 is sixth in GTLM, around where it was running before their move. The #33 Mercedes and #63 Ferrari are second and third, respectively, in GTD, an impressive gain that gets them back to where they were running before being caught off guard in the first place.

Hour 4:32, Full Course Caution 3: The #66 Ford, the GTLM leader, is stuck deep in the gravel. That's catastrophic for that car, which doesn't seem too damaged but has presumably knocked itself out of contention for a class win.

Since the #66 was stuck for so long, most of the field stopped before the safety car. This will normalize most teams onto the same strategy, so we'll never know if the #31's plan would have panned out without the help of the safety car.

Hour 4:30: The #31 is stopping earlier this cycle in what NBC is reporting is an attempt to normalize that car onto the same sequence to avoid being caught off guard by a safety car. Essentially, that car is giving up a full stop of time, which is a thing you can only do when you comfortably have the fastest car on the track and there are six hours left in the race. Impressively bold.

Hour 4:25: Penske Racing, if you haven't heard, is a little detail oriented:

Hour 4:22: The #62 Ferrari of Risi Competizione and driver Alessandro Pier Guidi appears to have caught the two Ford GTs, which had previously been running in the GTLM lead under relatively little pressure. All three are now covered by less than two seconds.

Hour 4:17: It's time to watch the #77 Mazda, which has gained ten seconds on the #5 Cadillac over the last hour. The gap is nine seconds for the overall lead, with that car trying to be the first non-Cadillac to lead today.

Hour 4:09: The #4 Corvette and #85 Cadillac DPi make some contact in a bout of yellow car on yellow car violence, but both cars return to the track with no visible damage.

Juan Piedrahita, driver of the #85 at the time of the incident, is awarded a drive-through penalty for that contact.

Hour 4:05: For those keeping score at home, the following cars are on aggressive alternate strategies:

DPi: Cadillac #31

GTLM: Porsche #911

GTD: Mercedes #33, Ferrari #63

You'll see these cars swing aggressively from the lead to around fifth in their respective classes about once every 40 minutes, but all four have just stopped, so your leaders in those classes are again the #5 Cadillac, the #67 Ford, and the #96 BMW, respectively.

Hour 4:00: The #911 Porsche, which led in GTLM for the last 20 minutes as it runs on its own strategy, undergoes a brake pad depth check during its stop. Brake changes are commonplace on GT cars during 24 hour races, but should not be an issue during a 10 hour race, so any choice to make a change here would come as a surprise.

The #67 and #66 Ford GTs return to their position running 1-2 in GTLM.

Hour 3:55: The #33 Mercedes and #63 Ferrari are still fighting on track, somehow, for what is the lead in GTD as they run but will likely cycle out to fifth in class once those cars make their next stops. After another momentary side-by-side scuffle, the #63 comes out leading the two yet again.

Hour 3:53: Felipe Nasr has the #31 up to third overall on track. These passes for position matter because Nasr's car is fast enough that he could gain enough time to win the race even if the team's strategy leaves it taking an extra stop.

Hour 3:48: Mike Conway, the stellar Toyota factory Prototype driver and multi-time IndyCar race winner, makes an uncharacteristic mistake and goes off at turn 10 from the overall lead. Conway lost around five seconds after that incident, but the #5 Cadillac seems to have escaped without a major issue.

His teammates in the #31 are up to fourth on track after a recent pass on the championship-leading #6 Acura, still in position to cycle into the lead when the cars on the other strategy stop.

Hour 3:40: Thanks to two lap-down cars, the battle for second in GTD was briefly four wide. The #48 Lamborghini maintains the position over the #86 Acura after an exceptionally bad idea of an attempted pass.

Hour 3:30: The #31 cuts its losses, with the team calling Pipo Derani to pit even earlier than last stint, taking that car further off strategy but, crucially, getting it away from the #10. Felipe Nasr is back in the car, where he should have a clean track for a few laps before he catches Graham Rahal in the #7 Acura.

The #50 Juncos Cadillac is behind the wall, tending to whatever issue casued it to stop on track in a precarious position a few minutes ago.

Hour 3:28: Pipo Derani has lost a fairly large chunk of his lead over the past two laps, and, given that he's on a more aggressive fuel strategy than anyone else, is getting to the point where he'll probably need to make an aggressive move on the #10 soon. As of yet, he's been patient.

Hour 3:25: The #31 is back in the overall lead, but it is somehow still behind the #10 on track. Pipo Derani is trying to put that car a lap down, but it will almost certainly be harder than it should.

Hour 3:21: The #55 Mazda's issue was a misfire about an hour earlier, previously unreported on the TV broadcast. It had already been behind the wall before its most recent issue, and returned after a second problem. It's bad news for one Mazda, but the other is very much in this race with a chance to win.

Hour 3:20: The #31 Cadillac, which is on a different strategy but should still cycle out as the leader, is locked in a dogfight for seventh it really doesn't need to be in at all. After about four attempts, Pipo Derani has finally cleared the #10 Cadillac, and now sets his sights on the #7 Acura.

The #50 Juncos Cadillac is stopped under the bridge at turn 11, the track's high speed final corner. Fortunately, it resumes and re-enters the pit lane without issue.

Hour 3:17: Mazda #55 is behind the wall with some sort of engine issue. It had been relatively off the pace, particularly with how well the #77 has been doing.

Hour 3:14: The #63 Ferrari is off track again, after what looks like a good bit of side-to-side contact from the #33 Mercedes AMG GT3. This race is suddenly action packed, and all thanks to GTD cars.

Riley Motorsports endurance driver Felipe Fraga, currently in that Mercedes, has been responsible for no small part of that.

Hour 3:10: The #63 Ferrari, still a very real contender in GTD, now has a single piece of massive tape keeping its right-front fender together. There are still nearly seven hours left in this race.

Hour 3:02: The #9 Pfaff Porsche is back on track after an off that seemed destined to end in the wall. Thankfully, it did not, but it marks yet another GTD car in a small bit of trouble near the front of the field.

Hour 2:58: Speaking of extremely fast GTD cars, the #33 Mercedes has a high speed off from eighth in GTD. That could be a big problem for that car, as could the minor damage the #63 Ferrari received from its contact with that Audi R8, which has just received a drive-through penalty for its unsuccessful block attempt shortly before that pass.

Hour 2:55: The #63 Scuderia Corsa Ferrari made some contact with the #29 Montaplast by Land Audi in the process, but it's moved back up to sixth in GTD. That's still one of the three fastest cars in that class.

Hour 2:51: Back to green. Derani has the #31 comfortably in the lead yet again. After the upheval caused by the timing of that safety car, the #96 Turner Motorsports BMW M6 is leading in GT3, while the #48 Lamborghini is the only car of the three entries that had dominated the majority of the race left in a provisional podium spot.

The broadcast has switched to an online-only stream for the next two and a half hours, resuming afterward on the NBC Sports Network.

Hour 2:37, Full Course Caution 2: The #12 Lexus slows to a stop in the grass outside of turn 1 with what appears to be a destroyed front-right suspension corner. The car was on its first flying lap and seems to have lost control while being passed by the #10 Cadillac, with the two possibly having made contact. The safety car is out.

This is particularly brutal for NBC Sports announcer Townsend Bell, who was scheduled to be racing that car later today. Bell was in the booth when the collision happened, and was able to react to the race-derailing issue in real time.

Hour 2:32: At this point, there seems to be a clear difference between the fully professional and pro-am classes; GTLM and DPi are both very stagnant, with nobody with a healthy car falling out of contention but nobody pushing hard to decrease any gaps or make any major passes. GTD, meanwhile, has on a few occasions been a hornet's nest, and even as the #48 Lamborghini again pulls away with a comfortable lead while the #33 and #63 are on a different strategy, the #96, #9, and #86 are within just two seconds in a battle for second on track. Expect that to be the pattern for much of the race, with the real contenders in GTLM and DPi not being completely clear until we see who's left on the lead lap in about four hours.

Hour 2:18: The #5 Cadillac, running in second, finally makes its first driver change during this set of stops, with Filipe Albuquerque giving way to Mike Conway. The Toyota LMP1 factory driver will have a moderate gap to the leader, but he's out ahead of the #6 Acura, so he should have an open track as he attempts to catch his teammate.

The #10 Cadillac of Wayne Taylor Racing, which employed Toyota drivers Fernando Alonso and Kamui Kobayashi en route to a win at Daytona earlier this year, has received a drive-through penalty for speeding during its stop. That car is running sixth on track and is certainly still in contention for an overall win.

Hour 2:05: The lone remaining LMP2 car, the #52 of Dalton Kellett and PR1 Mathiasen Motorsports, seems to have lost a tire. This happened in the very middle of the still-raging battle for the GTD lead, but thankfully neither the LMP2 car nor any of the GTD cars made any contact with anyone else.

Hour 1:59: The #33 Mercedes is clear into the GTD lead, but his move to get past the Ferrari actually opens the door for the #48 Lamborghini to take a shot at passing two cars at once into the tightest corner on the track. The Mercedes holds the inside line, however, and Riley Motorsports now has their car in the GTD lead.

Hour 1:56: The previous GTD leader, the #48 of Paul Miller Racing, has fallen to third on this restart, with the #33 Mercedes AMG GT3 of Riley Motorsports and the #63 Ferrari of Scuderia Corsa moving into second and first, respectively. The #9 Pfaff Motorsports Porsche, which will likely finish second in that class championship, is now just a few car lengths behind that Lamborghini with a shot at moving into third.

Hour 1:52: Honda factory driver Ryan Eversley, who has actually raced cars on this track in a world that is not digital, contends that the Castroneves incident was more avoidable than the television cameras made it seem. Going to go ahead and assume I'm wrong on this one:

Hour 1:48: The #14 AIM Autosport Lexus and #44 Magnus Racing Lamborghini make high speed contact on the back half of the course, but both stop before getting to the wall and both resume without any further issue. An impressive lack of dmage for a high-speed racing incident between GTD drivers fighting for position.

Hour 1:45: Back to green. Another strong start for the #31 Cadillac, as Pipo Derani runs away from the field on the restart.

Filipe Albuquerque struggles on the start in the #5 Cadillac, and Juan Pablo Montoya pounces to jump to second. The #55 Mazda runs fourth, the #10 Wayne Taylor Racing Cadillac lies in wait in fifth.

The #7 Acura, which was running in the top four the entirety of the race, is still running on the lead lap after its bodywork change, but it will lose a significant chunk of time to take a just-announced drive-through penalty for what can only be described as "Hitting a car that was unavoidable." Interesting bit of officiating happening there!

Hour 1:35, Full Course Caution 1: All three major classes have completed their cycles of stops under this safety car, and, while the leaders remain the same in DPi and GTD, the two Chip Ganassi Racing Ford GTs were able to take advantage of their larger fuel loads going into this cycle of stops to leapfrog the Risi Competizione Ferrari for the GTLM lead. Everyone is running on the same strategy now and the fixable damage to the #7 Acura means that only the #24 BMW in GTLM has suffered a major setback among contenders, so this is a bit of a reset with just, uh, eight and a half hours to go.

Hour 1:26, Full Course Caution 1: NBC has found a replay, and it shows that the #7 Acura made hard contact with the #38 LMP2 car because that car panicked and slowed excessively while being passed by the #6 Acura. The slower car was running well off the pace when the #7 came over the hill, and, between the lack of time to react and the lack of track to escape to, Helio Castroneves was unable to avoid hitting it.

The driver of the #38 was moving immediately after the collision, but the car is presumably done for the day. The #7 Acura, however, seems to only have damage to a piece of bodywork designed to be easily interchanged anyway.

Hour 1:24, Full Course Caution 1: The #38 Performance Tech Motorsports LMP2 car is stopped on track after a major collision. That car seems to have lost control in the esses, backing into a concrete wall at high speeds. The car is damaged, seemingly beyond repair, and the safety car is out for the first time today.

The #7 Acura of Helio Castroneves, running fourth overall, has major damage to its front bodywork. One can reasonably guess that these two things are related.

Hour 1:23: Would you like to see a good video of a racing car doing a neat thing? Well, here you go:

Hour 1:15: Cadillac #5, running fourth overall, makes a little bit of contact with one of the "Banana Boat" JDC Miller Cadillacs under braking. That car is running second overall and cannot risk even light contact if it has any hope of dismantling the #31's 20 second lead.

Hour 1:10: Acura #6 starts the second round of stops. This is the championship leader, so it shouldn't be as surprise that it is running a relatively conservative fuel strategy. Juan Pablo Montoya is getting in that car, which is already more than half a lap behind the overall leader.

Hour 0:55: Ferrari #63 comes out ahead of Lamborghini #48. Unfortunately for Cooper MacNeil, Bryan Sellers is now in that Lamborghini, and Sellers needed just one lap more heat in the tires to get back to the net GTLM lead in just half a lap.

Hour 0:53: The GTD leader stops, and, with the gap in that class never really getting larger than a second, these next few laps will be very interesting in that class. This marks a prime opportunity for the #63 Ferrari to pass that #48 Lamborghini, either virtually over the course of the cycle or on track when both are on cold tires.

Hour 0:42: GT stops begin. The #911, which was running fifth on track, begins the process.

Hour 0:45: The #24 BMW M8 GTE goes behind the wall. That car was running second in GTLM, and had been resurgent since switching back to the black livery that team had run with such success when that team ran the old Z4 GTE.

No word yet on what the issue is, but that can't be a good sign.

Hour 0:32: DPi stops begin. There will be many of these today.

Cadillac #31 is not among the first to pit, meaning that the car will have a lap of fuel on some of the stronger contenders on top of its massive lead. A strong effort for that car so far.

Hour 0:30: Not much action on track through thirty minutes, which means it's time to check on LMP2! The #38 Performance Tech car is out front by nine seconds. Somehow, these races seem to have been decided by 5 laps every week. Will that be the case today? Only time will tell for these two cars that would under last year's rule set have been running 10th and 11th in DPi but are now technically fighting for a win worth just as much as the all-out war between nine factory cars in GTLM.

Hour 0:17: The lead in DPi is up to twelve seconds. That's quite a lot, especially for a class with two other cars of the same make and year easily capable of winning this race in the field.

GTD is now the best battle on track, with the #48 Paul Miller Racing Lamborghini having pulled away from everyone but the #63 Scuderia Corsa Ferrari, which runs just a half a second behind.

Back in second in DPi, the #7 Acura, which started on the front row, is now down to fourth on track after making a mistake in traffic. That means the #6 Acura, the one leading the championship race, is now running in a provisional podium spot.

Hour 0:10: The DPi lead is already up to four seconds, and the #7 Acura is under fairly significant pressure from the #5 Action Express Cadillac for second. That team is expected to run just one full time car next season, and it is not expected to be the #5, so a win here would mean quite a lot for Joao Barbosa and Filipe Albuquerque.

James Calado has a 2 second lead in the #62 Risi Competizione Ferrari in GTLM, while the #48 Lamborghini of Paul Miller Racing has a lead of around a second in GTD, with four seconds further to third. A strong start for pole sitters in the three major classes.

Hour 0:02: Jon Bennett, the driver-owner of CORE Autosport, has spun that car's Nissan DPi in what is assumed to be the last-ever race for both that car and that driver, has spun entering the final corner. The car resumes with no damage, an impressive feat given how fast that corner is. Bennett's team is expected to end prototype operations after this season, but the team will continue to run Porsche's GTLM factory program.

Hour 0:01: Green flag. The #31 Cadillac pulls into an early lead in DPi. Felipe Nasr is in that car and has pulled a strong lead over the #7 Acura DPi through half a lap.

Hour 0:00: As has been the case since the inception of this race, the domestic sports car season ends as it began, with an endurance race.

The Petit Le Mans is the least historic of the four major endurance sports car races, and, since the Rolex 24 integrated the ALMS grid and the LMP1 heavyweights stopped coming overseas for the other American endurance events after the ALMS-Grand-Am merger, it is easily the least famous as well. That does not stop the day-int0-night epic from being routinely spectacular. That's in no small part due to its traditional venue, Road Atlanta, a fast, flowy track that captures what makes the sort of natural terrain road course American sports cars frequent so fascinating while maintaining a much higher average speed than a Sebring. The time of year and location also introduces the annual element of looming rain, something that has in the often never come, but has on two occasions this decade transformed the race so dramatically that the results would make no sense without knowing the race was run in soaking conditions. It's long, it's unpredictable, and it decides year-long championships.

The biggest of those will be in DPi, a class that has had three notable eras over the course of the season. The first was of Cadillac dominance, but a Balance of Performance update early in the season radically shifted that to a focus on the sudden rise of the previously-snakebitten Mazda program at the Six Hours of the Glen. The program rattled off three wins in a row after going winless since joining the top class of IMSA competition, but, when the category resumed from a short Summer break for a GT-only race at Lime Rock, Mazda's dominance was gone, and an even field saw a Penske Acura return to victory lane with relative ease. That car, the one of Dane Cameron and Juan Pablo Montoya, enters today with the championship lead, by twelve points over the #31 Cadillac of Pipo Derani and Felipe Nasr. Unfortunately for Team Penske, the #31 starts from pole today, and, while the #7 Acura has the luxury of starting on the front row, the series-leading car is actually the #6, which starts in fourth. The top six represent all three major manufacturers in the class, but only the #6 Acura and #31 Cadillac can win the title.

LMP2 has been a two-horse race all season, but not because of a spectacular duel between top contenders or anything. There are simply just two cars in the class. PR1 Mathiasen leads the standings by eight points, and, because Performance Tech Motorsports has the only other entry in the class, that championship will be over the moment the race begins. If you're interested in checking in on something once every two hours, this might be the class for you to watch from the corner of your eye, though for most of the season these races have not been particularly close.

GTLM is very much contingent on whether or not the #912 Porsche finishes the race. It has a 12 point lead on its teammate, #911, meaning they need to finish just seventh of nine in class. If they do not, the door is suddenly open to the #911, while the #3 Corvette and both Ford GTs are within reach of second. None of those contenders will be starting on the front row, however, with the #62 Risi Competizione Ferrari starting on pole next to the #24 BMW M8 GTE, which inherited that position after the #3 Corvette was penalized after qualifying and sent to the back of the grid. This marks the last race for the Corvette C7.R, and, likely, the last full-time entry for Chip Ganassi Racing's Ford GTs, which the team are hoping will run at least a limited schedule next year, though no plans have officially been made as of yet.

GTD will be decided when the #86 Acura starts the race.

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