Porsche are headed for a third successive victory at the 24 Hours of Le Mans after early pace-setters Toyota saw their hopes of a first win disappear before dawn.
The Graff Racing entry of Australian James Allen, Franck Matelli and Richard Bradley was ninth overall after the 17 hours mark, while the Ford of Aussie Ryan Briscoe, New Zealand's Scott Dixon and Richard Westbrook was 26th overall and eighth in the GTE Pro class.
In an agonising half hour for Japanese manufacturer Toyota, whose hopes were high after securing pole position with a record fastest lap at the Sarthe circuit, two of the team's three cars retired in the night.
Only the number eight Toyota remained on track, in 15th place and 28 laps behind the leading Porsche of former winners Neel Jani of Switzerland, Britain's Nick Tandy and Germany's Andre Lotterer.
"It is so disappointing. The car was running very well and we were just taking things steady, building a gap at the front. Then after the safety car, I just had no power," pole-sitter Kamui Kobayashi said.
The former Formula One driver was halted by a clutch problem in the leading number seven car around the 10 hours mark.
Until then, the car had barely missed a beat as five-times runner-up Toyota set about trying to end years of heartache and become only the second Japanese manufacturer to win the motor sport's greatest endurance race.
The team missed out last year when their leading car broke down on the final lap only minutes from the chequered flag.
In a second big blow, the number nine car driven by Frenchman Nicolas Lapierre, Japan's Yuji Kunimoto and Argentina's Jose Maria Lopez was involved in a collision 15 minutes later and was forced to retire.
The number eight car of Switzerland's Sebastien Buemi, Britain's Anthony Davidson and Japan's Kazuki Nakajima had already lost more than an hour in the pits as mechanics replaced the front motor and battery.
With Toyota out of the picture, the stage was set for Porsche to win by a massive margin.
Two LMP2 cars were in the other podium spots, with the Jackie Chan DC Racing Oreca driven by Thomas Laurent, Oliver Jarvis and Ho-Pin Tung in second place, 12 laps behind.
Vaillante Rebellion's number 13 car, driven by Nelson Piquet Junior, David Hansson and Mathias Beche was third.