The #51 Ferrari 499P was holding a comfortable lead of some 47 seconds at the head of the field over the Peugeot of Nico Muller when Pier Guidi lost control heading into the first chicane on the Mulsanne straight.
Pier Guidi appeared to be trying to avoid another car that had gone off track ahead of him, and his car needed assistance from the recovery vehicles to get back on track.
That handed the lead of the race to Muller in the #94 Peugeot 9X8 ahead of the #50 Ferrari of Nicklas Nielsen, who had been delayed by an off during a rain shower that hit the Circuit de la Sarthe just after the six-hour mark.
Moments later, there was further drama at Tertre Rouge as the #7 Toyota of Kamui Kobayashi appeared to be involved in a collision with the #66 JMW Motorsport Ferrari of Louis Prette and the #35 Alpine LMP2 car of Memo Rojas.
Kobayashi, who stood to move up into second prior to the incident, was initially struggling to coax his Toyota GR010 HYBRID back to the pits.
But the Japanese driver was then seen parking up on the Mulsanne straight and exiting the cockpit, signifying the end of the road for the #7 car he shares with Jose Maria Lopez and Mike Conway.
That promoted the Cadillac of Earl Bamber to third place behind Nielsen's Ferrari, with Pier Guidi finally resuming in fourth, still on the lead lap.
Toyota's sole surviving car, the #8 machine of Ryo Hirakawa, is the final car on the lead lap in fifth place.
Earlier on, Porsche suffered the first official retirement of the race in the Hypercar class as the #75 machine of Mathieu Jaminet came to a halt with fuel pressure problems and was unable to resume.
