Under overcast skies, with the wind blowing and rain picking up in pulses around the 8.469-mile, 38-turn Circuit de la Sarth, the 81st running of the Le Mans 24 Hour race officially got underway with the tricolour flag waved by Bill France at 3pm local time (2pm BST).

The #2 Audi R18 e-tron quattro driven by Allan McNish lead the field across the line alongside his Audi Sport Team Joest stablemate Andre Lotterer in the #1 car. Lotterer got the better run around the outside and immediately took the lead, while behind them the #7 Toyota TS030 hybrid driven by Nicolas Lapierre managed to pounce two cars to slip into third place ahead of the #3 Audi (Lucas di Grassi) and the #8 Toyota (Anthony Davidson).

Lapierre continued to press the advantage and quickly moved into second place ahead of McNish, while Davidson quickly picked up the pace and passed McNish to take third place in an unexpectedly strong start for the Toyotas against the might of the Audis. Lapierre even made a play for the lead on lap 2, only to be repulsed by Lotterer again at Arnage.

Given the treacherous conditions it was no surprise that the first safety car was out just ten minutes into the race. The cause was the #95 Aston Martin Vantage V8 GTE-Am front runner, after Allan Simonsen spun off at Tertre Rouge. He took a hard hit against the barrier, demolishing the car and forcing full safety extraction and medical response teams to scramble. Simonsen was reported to be awake and talking with medics, but was transported to the hospital for further evaluation.

Simonsen's accident handed the class lead to Patrick Long in the #77 Dempsey Del Piero Porsche, while Darren Turned headed the GTE-Pro field in the #97 Aston Martin Vantage V8 and Olivier Pla held LMP2 honours in the #24 OAK Racing Morgan-Nissan.

The #25 Delta-ADR ORECA-Nissan driven by Shinji Nakano, running in fifth place in the LMP2 field, dived onto pit road for some prolonged urgent gearbox work in the garage while the race was running under yellow. Another of the LMP2 cars, the #48 Oreca 03-Nissan driven by Brendon Hartley, also hit electrical problems and needed to pit briefly from sixth.

The ensuing delay for barrier repairs was a lengthy one and saw out the remainder of the first hour of the event, although few teams took the immediate opportunity to pit for fuel or driver changes this early in the day. The multiple safety car system used at Le Mans meant that the GTE-Pro field in particular was split in two.

LMP1 leaders

1. #1 Lotterer/Fassler/Treluyer Audi Sport Team Joest Audi R18 e-tron quattro * 9 laps (0 stops)
2. #7 Wurz/Lapierre/Nakajima Toyota Racing Toyota TS030 hybrid * 9 laps (0 stops)
3. #8 Davidson/Buemi/Sarrazin Toyota Racing Toyota TS030 hybrid * 9 laps (0 stops)

LMP2 leaders

1. #24 Pla/Heinemeier Hansson/Brundle OAK Racing Morgan-Nissan * 9 laps (0 stops)
2. #47 Imperatori/Tung/Howson KCMG Morgan-Nissan 9 laps (0 stops)
3. #38 Dolan/Turvey/Luhr Jota Sport Zytek-Nissan 9 laps (0 stops)

GTE-Pro leaders

1. #97 Turner/Mucke/Dumbreck Aston Martin Racing Aston Martin Vantage V8 * 9 laps (0 stops)
2. #92 Lieb/Lietz/Dumas Porsche AG Team Manthey Porsche 911 RSR * 9 laps (0 stops)
3. #99 Bell/Makowiecki/Senna Aston Martin Racing Aston Martin Vantage V8 * 9 laps (0 stops)

GTE-Am leaders

1. #77 Dempsey/Foster/Long Dempsey Del Piero-Proton Porsche 911 GT3 RSR 9 laps (0 stops)
2. #67 Gibon/Milesi/Henzler IMSA Performance MATMUT Porsche 911 GT3 RSR 9 laps (0 stops)
3. #61 Gerber/Griffin/Cioci AF Corse Ferrari 458 Italia * 9 laps (0 stops)

* - denotes World Endurance Championship entrant

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