Audi scored its 13^th victory in 15 attempts at the Le Mans 24 Hours, and Andre Lotterer, Benoit Treluyer and Marcel Fassler their third in four years, but only after one of the most dramatic races in the grand euduro’s long history.

Pre-race favourite Toyota suffered heartbreak after dominating until the early hours of Sunday morning, once the chaos and carnage caused by flash storms in the opening hours subsided.

An electrical failure left pole winner Kazuki Nakajima stranded out on the circuit in his TS040 Hybrid at 5am, as the race swung towards the eventual victors – only to seemingly slip away again with an enforced change of turbo for the Audi R18 e-tron quattro.

The sister car picked up the baton, with Tom Kristensen on course to extend his incredible win record to 10.

But in a race of attrition, the Dane’s car – newly built after team-mate Loic Duval’s horrific qualifying crash – required its own turbo change, raising hopes of an unlikely victory for Porsche in its long-awaited return to the race it has won more than any other manufacturer.

Porsche’s 919 Hybrid took the lead as Audi’s crew went to work on Kristensen’s car. But a charging Lotterer had Timo Bernhard in his sights to take the lead back as Mark Webber took over for the final stints. The former Red Bull Grand Prix driver was powerless to contain the flying Audi – in the most literal respect as the 22^nd hour turned.

A dream podium was lost as Webber toured into retirement, with an engine problem that disabled his 919.

That left Treluyer to finish the job for the no 2 Audi, as a recovering Kristensen, Lucas di Grassi and Marc Gene completed a remarkable – and for once – unlikely one-two for the Four Rings.

Team principal Dr Wolfgang Ullrich said: “The turbo is something we have won with here and in the World Endurance Championship many times, and we’ve never had a problem with it. But today two broke. More than any other year, it’s been a huge team effort this week.”

Just as remarkably, Anthony Davidson, Nicolas Lapierre and Sebastien Buemi salvaged a podium finish for Toyota, after severe damage from an accident during the flash storms left the crew playing catch-up from the second hour.

As expected, Alex Wurz had turned Nakajima’s pole position into a comfortable lead from the start, as the sister Toyota, the two Porsches and the three Audis put on a stunning display of wheel-to-wheel racing.

Nissan’s innovative ‘Garage 56’ ZEOD entry was the first casualty, having achieved its aim of reaching a top speed of 300kph in qualifying and achieving the first all-electric powered lap of Le Mans in the morning warm-up.

Porsche would be the first of the ‘Big Three’ to suffer a major setback as the no 14 car of Neel Jani, Romain Dumas and Marc Lieb was hit by fuel pressure problems. The car recovered to fourth in the closing stages, as the dramas played out ahead of it, but gearbox problems would rob the prototype team of a consolation result in the final hour.

The flash storms caught everyone out in the second hour, and wrought early drama that would shape the race. Marco Bonanomi had impressed during the opening salvos in the no 3 Audi shared with Oliver Jarvis and Felipe Albuquerque. The third entry had raised eyebrows by outqualifying its more illustrious sisters, but its race would end abruptly on the Mulsanne after just 24 laps.

Bonanomi had slowed to a crawl in the sudden downpour as behind him Lapierre lost control of his Toyota. The Japanese entry tagged the R18 during its own major accident, then Sam Bird’s GTE AM class-leading Ferrari slammed into the Audi with major force.  Both were out on the spot, as Lapierre nursed his TS040 Hybrid back to the pits with major frontend damage.

“It was an epic race with three top manufacturers leading at one time or another,” said a disappointed Davidson. “Any one of us could have made the mistake but there are lessons to be learned.”

A second flash storm in the third hour forced another safety car period, which not only negated Wurz’s advantage but would also lose him the lead as fuel strategies became convoluted by the pause in action.

Class podiums

LMP1
1. Fässler/Lotterer/Tréluyer (Audi)
2. Di Grassi/Gené/Kristensen (Audi)
3. Buemi/Davidson/Lapierre (Toyota)

LMP2
1. Dolan/Tincknell/Turvey (Jota-Zytek)
2. Badey/Gommendy/Thiriet (TDS-Ligier)
3. Chatin/Panciatici/Webb (Signatech-Alpine)

GTE Pro
1. Bruni/Fisichella/Vilander (AF Corse-Ferrari)
2. García/Magnussen/Taylor (Corvette)
3. Holzer/Lietz/Makowiecki (Manthey-Porsche)

GTE Am
1. Hansson/Poulsen/Thiim (Aston Martin)
2. Al Qubaisi/Bachler/Ried (Proton-Porsche)
3. Cioci/Companc/Venturi (AF Corse-Ferrari)

Bernhard, who had been running third for Porsche, took some glory by leading the race, but an unscheduled stop for a puncture with Hartley at the wheel would restore the natural order in the fifth hour, by which time warm and sunny conditions had returned to the Circuit de la Sarthe.

Wurz, Nakajima and Stephane Sarrazin would lead through the night, although in a role-reversal from last year’s race they were constantly kept on alert by the presence of the two remaining Audis, which kept the Toyota in striking distance. A tense and lengthy stalemate ensued, which in its own way was almost as spellbinding as a wheel-to-wheel fight.

The tension broke when Nakajima’s electrical woes brought Toyota’s hopes of breaking its Le Mans duck to a sudden halt. “It is heartbreaking,” said the Japanese. “Somehow I thought we would make it this time and then this happens.”

The no 2 Audi inherited the lead, until 7am when it was forced to stop for 23 minutes for a turbo change. It’s been a long time since a Le Mans-winning car has come back from such a pitstop delay.

“If you lose five laps, as we did, it’s usually impossible to get them back,” said Fassler. “But everyone had problems today.”

Now Kristensen, who’d shown typical inspiration in no 1 through the night after the car had been delayed by a fuel injector problem, held the upper hand. But just after 11am all thoughts about that magic 10^th victory were dashed.

The Dane stopped on the Mulsanne to reboot his car’s systems, then struggled on. The subsequent stop for a new turbo was completed five minutes quicker than it had taken for the sister car, but from now on Kristensen and co knew they would play a supporting role to the main drama ahead of them.

Porsche’s chances of fending off Lotterer’s Audi were always slim given the superior pace of the R18. But Webber’s retirement ensured Audi could finally concentrate solely on survival rather than its rivals.

Just off the podium, Rebellion Racing recorded a remarkable fourth place with its new R-One privateer LMP1 prototype, which ran without hardly a murmur in the hands of Nick Heidfeld, Nicolas Prost and Mathias Beche. “It was only seven weeks ago this car first ran,” said Heidfeld. “To finish fourth against seven manufacturer cars is fantastic.”

The classes offered no less excitement, as usual.

The new Ligier JS P2 looked on course for a remarkable debut victory on the marque’s return to Le Mans. The G-Drive OAK racing entry of Alex Brundle, Jann Mardenborough and Mark Shulzhitskiy fought most of the way with the pole-winning TDS Racing Ligier led by Tristan Gommendy, but it was the British Jota Sport team and its Zytek-Nissan that made a late charge after early delays to steal the victory in the final hour.

For Oliver Turvey, victory was particularly sweet. At the beginning of the week, he’d lost his supposed drive when Millennium Motorsport had pulled its entry. But in the wake of Duval’s accident on Wednesday, Audi recalled Marc Gene who’d been down to drive for Jota. That opened up a seat, and a chance for Turvey to return to the team with which he raced in the European Le Mans Series last year.

It was fitting that it should be Turvey who completed the final stint, jumping into the lead at the final pitstop and holding off the TDS Ligier. He shared the win with team boss Simon Dolan and Harry Tincknell, who put in a stellar performance on his race debut.

Gianmaria Bruni, Giancarlo Fisichella and Toni Vilander repeated their victory from 2012 in the GTE PRO category. The biggest challenge to their AF Corse Ferrari 458 was the Aston Martin Vantage of Darren Turner, Stefan Mucke and Bruno Senna, which set the pace in the category. The two cars engaged in a superb battle, until the Aston hit power steering problems and its challenge faded.

But Aston did at least claim GTE AM, with the all-Danish line-up of Kristian Poulsen, David Heinemeier Hansson and Nicki Thiim proving dominant. A year on from the death of Allan Simonsen, this was the most emotional and heart-warming story of an amazing day, one that won’t be forgotten by drivers, teams and fans alike.