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.
Porsche headed for a third successive victory at the 24 Hours of Le Mans on Sunday after early pace-setters Toyota saw their hopes of a first win disappear before dawn.
In an agonising half hour for the Japanese manufacturer, 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," said pole-sitter Kamui Kobayashi.
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 runners-up Toyota set about trying to end years of heartache and become only the second Japanese manufacturer to win the world'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.
Kobayashi got going again momentarily before the car stopped again and he had no option but to park up and walk away.
"I tried to come back to the pits but it wasn't possible. I feel so sad for everyone in the team who has worked so hard for this race and produced such a quick car," he said.
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.
The impact at the approach to the first corner at around 1.30 a.m. caused too much damage to continue.
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 France's Thomas Laurent, Britain's Oliver Jarvis and Dutch-born Chinese racer Ho-Pin Tung in second place but 12 laps behind.
Vaillante Rebellion's number 13 car, driven by Brazilian Nelson Piquet Junior, Denmark's David Hansson and Switzerland's Mathias Beche was third.
The second Porsche of New Zealanders Earl Bamber and Brendon Hartley, along with Germany's Timo Bernhard, was out of contention 18 laps behind after suffering front axle problems.
(This article has not been edited by DNA's editorial team and is auto-generated from an agency feed.)
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