A late-race penalty didn’t deny Marcel Fassler victory, as Audi held off strong challenges from Porsche and Toyota to claim top honors in Sunday’s Six Hours of Silverstone.

The thrilling season-opening round for the FIA World Endurance Championship saw a titanic three-manufacturer fight for nearly the entire race that went right down to the wire, with the top three finishers separated by less than 15 seconds at the checkered flag.

Fassler took his No. 7 Audi R18 e-tron quattro to a narrow 4.610-second victory over the No. 18 Porsche 919 Hybrid of Neel Jani, who cut the gap in half in the final 15 minutes of the race.

It came following the penalty for the Swiss driver for abusing track limits with advantage while battling with Jani for the lead prior Fassler’s final fuel-only stops.

Despite having to make two consecutive trips down pit road, Fassler retained the lead over the Porsche, which pitted more than 30 minutes earlier, out of sequence compared to the Audi and Toyota.

The win for the No. 7 car of Fassler and co-drivers Andre Lotterer and Benoit Treluyer marked a return to form for the German manufacturer, in one of the most hard-fought FIA WEC races in recent memory.

Additionally, the trio claimed the Royal Automobile Club Tourist Trophy.

Jani, Marc Lieb and Romain Dumas settled for second in their No. 18 Porsche, with the No. 1 Toyota TS040 Hybrid of Sebastien Bueumi, Anthony Davidson and Kazuki Nakajima completing the podium.

All three cars fought tooth-and-nail from the third hour, following a frantic start to the race that saw the pole-sitting No. 17 Porsche of Mark Webber bridge out nearly a 20-second lead.

However, drivetrain failure in the second hour resulted in early retirement for the race favorite.

Despite also facing setbacks, the second entries from Toyota and Audi managed to finish fourth and fifth, respectively.

G-Drive Racing claimed a 1-2 class victory in LMP2, with the No. 26 Ligier JS P2 Nissan of Sam Bird, Roman Rusinov and Julien Canal taking top honors following a dominant performance virtually from the start.

Bird took over the lead on Lap 6 and the Russian-backed squad didn’t relinquish it from that point, cruising to a two-lap win over the pole-sitting sister No. 28 car of Gustavo Yacaman, Pipo Derani and Ricardo Gonzalez.