Juan Pablo Montoya held a small lead over Felipe Nasr as the sun went down over Michelin Raceway Road Atlanta heading into the final four hours of Motul Petit Le Mans.
Montoya entered the long period of darkness as the leader of the 10-hour race in the No. 60 Meyer Shank Racing Acura ARX-05 that he shares with Dane Cameron and Helio Castroneves.
The Colombian was coming under pressure from Action Express Racing Cadillac driver Nasr, who took the restart from the seventh caution period of the race in third but advanced to second with an overtake on Wayne Taylor Racing’s Alexander Rossi.
Earl Bamber climbed to third for Chip Ganassi Racing after making a brilliant charge through DPi field at the restart.
That yellow was called for debris after Bamber, on his out-lap from a pit stop, came together with JDC-Miller Motorsports Cadillac driver Loic Duval through the Esses.
Bamber made an emergency pit stop with right-rear bodywork damage but remained on the lead lap when the rest of the DPi field came in during the caution period.
The New Zealander, who was drafted into Ganassi’s lineup on race day morning, then passed Jimmie Johnson for fifth at the restart just before five and a half hours.
He went on to dispatch Duval and Rossi to reach third, leaving him eight seconds behind Nasr in the No. 31 Whelen Cadillac.
Another driver on a charge was Harry Tincknell, whose Mazda RT24-P returned to the lead lap during the seventh caution after losing ground due to a spark plug issue.
Tincknell gained three spots to enter the most recent yellow in the fourth behind Montoya, Nasr and Bamber, with Duval fifth for JDC-Miller and Rossi sixth aboard the Wayne Taylor Acura.
The six-hour mark passed under safety car conditions after Ligier JS P320 Nissans from United Autosports and Performance Tech Motorsports ground to a halt at different points on the track, marking the eighth caution of the event.
Thomas Merrill led Scott Huffaker in a close LMP2 battle, with just one second separating the front-running WIN Autosport Oreca 07 Gibson from the equivalent run by PR1/Mathiasen Motorsports.
Four LMP2 cars were on the category’s lead lap with four hours remaining, with Tower Motorsport and United Autosports still in contention.
Alexander Sims moved into the GT Le Mans lead as his No. 4 Corvette Racing crew gained four spots in the pit stops that coincided with the seventh caution.
Sims led the green flag time between the yellows, ahead of Matt Campbell in the No. 79 WeatherTech Racing Porsche 911 RSR-19 and the No. 24 BMW M8 GTE with John Edwards at the wheel.
Edwards took the restart behind his teammate Bruno Spengler but found a way past the Canadian’s RLL-operated car.
Laurens Vanthoor took the GT Daytona lead in the championship-leading No. 9 Pfaff Motorsports Porsche 911 GT3 R shortly before the six-hour mark.
Vanthoor moved ahead of Alegra Motorsports Mercedes-AMG driver Daniel Morad to head up a class battle that was transformed after several front-runners retired in a multi-car accident after four hours.