Kamui Kobayashi leads a Toyota one-two at the end of six hours at the 24 Hours of Le Mans as its Hypercar class competitors struck trouble.
Kobayashi in the #7 Toyota GR010 Hybrid sits on a cushion of 3.5 seconds over stablemate Ryo Hirakawa at the wheel of the pole-sitting #8 Toyota with the race now heading into the night.
Next best is Glickenhaus Racing's #708 of Pipo Derani in third, though a lap down, while the #709 Glickenhaus and #36 Alpine Hypercar were delayed with separate problems.
Both cars spent time in the garage as the #709 Glickenhaus needed a faulty sensor replaced and the #36 Alpine suffered an issue with the electronic clutch unit before a trip through the gravel.
Sebastien Buemi led away from pole position in the #8 Toyota when the race got underway at 16:00 local time as the drama kicked off early.
When the LMP2 starting group accelerated away, front-row starter Will Owen became swamped by cars around his #22 United Autorsports Oreca.
Owen got sandwiched between the two WRT entries on the run into Turn 1 which resulted in contact and the United car in beached 10-seconds into the race.
While he was recovered from the gravel and rejoined two laps down, the #31 WRT machine was slapped with one minute stop and hold penalty for the incident.
As the action kicked off in LMP2, out front Buemi was eventually caught by the sister #7 Toyota of Mike Conway for the overall lead.
The pair traded positions in the first round of pit stops as Conway vaulted into the lead with a quicker pit stop on the #7 Toyota.
They ran that way for nearly two hours until another swap around in the fourth hour when Brendon Hartley found himself in the lead aboard the #8 Toyota.
Owing to a trip through the gravel for Jose Maria Lopez on his out lap in the #7, Hartley emerged from the pits with the sister car in his mirrors.
In the hour and a bit since Hartley has been able to control the pace at the head of the field having ticked over 70 laps of Circuit de la Sarthe at the six-hour point.
Following the three-car LMP2 collision at the start of the race, it was Robert Kubica in the #9 Prema Oreca that benefited and claimed the lead.
Akin to the Hypercar class, there was a change of lead in LMP2 in the first round of pit stops seeing the #38 JOTA entry come to the fore.
Antonio Felix Da Costa consolidated his new-found advantage out front over Kubica, however, deeper in the LMP2 field the racing was fierce.
Team Penske fought its way into second ahead of the Team WRT Oreca in third.
Sitting 19th in LMP2 is the #45 Algarve Pro Racing car featuring Australian driver James Allen.
In GTE-Pro, the Porsches managed to break up the Corvettes in the early stages but there was no slowing down the leading #63 Corvette.
Nicky Catsburg held onto a 40-plus second margin in the #63 at the six-hour mark after a faultless first quarter of the race.
The GTE-Am competition was dominated by Porsches at the head of the field during the opening hours as the pole-sitting #61 Ferrari dropped to ninth in the hands of Vincent Abril.
Julien Andlauer moved to the front of GTE-Am in the #79 WeatherTech Racing Porsche in the second hour and holds a significant lead.
A pair of Aston Martins have worked their way back into the mix courtesy of Northwest AMR and TF Sport in second and third respectively.
New Zealander Nick Cassidy drove a solid stint in the #54 AF Corse Ferrari which runs sixth, with Matt Campbell's #93 Proton Competition Porsche 20th in GTE-Am.
The race has seen a number of localised slow zones for minor incidents, but as yet, no major crashes.