Fabien Foret has given his slim World Supersport Championship hopes an unexpected boost after taking a much-needed first win of the season, while champion-elect Chaz Davies was forced to retire from a clear lead.

Davies looked to be on course for his sixth victory of the season, one that would have seen him wrap up the 2011 WSS title in style, only for the engine on his ParkinGO Yamaha to blow with five laps remaining whilst he was leading by a vast margin.

Eerily reminiscent of Cal Crutchlow DNF at this stage two years ago, it capped a frustrating day for the Italian team, ParkinGO having looked on course for a dominant 1-2 at one stage, only for Luca Scassa to retire from second before Davies's demise.

With Davies out, an already intense battle for second suddenly became the fight for the lead over the remaining five laps, a pack led intermittently by Florian Marino and Gino Rea during the first-half of the race.

However, their pace was not strong enough to maintain the gap they had built up to the chasing group, with Foret, who had started down in 12th, coming from a long way back to get himself back into the mix.

Indeed, a series of fast laps had Foret onto the tail of Marino, Rea, Sam Lowes - himself having fought back from a distance behind - and Broc Parkes with five laps to go. Almost simultaneously, Davies's retirement sparked the battle once more, with Lowes and Foret using their momentum to get to the front of this group and pull away.

With Lowes out front, it looked as though the Parkalgar Honda rider was on course for his maiden WSS win, but it was Foret who maintained the speed advantage, slipping through on the penultimate lap to move into a lead he'd hold to the chequered flag.

A remarkable result given Davies needed a mere third to secure the title regardless of his rivals' results, while Foret required nothing less than a win to keep his hopes alive, it means Foret will keep the fight going to Magny-Cours. Even so, with 35 points still between them, Davies remains very much the favourite for the title.

Lowes held on for second after a hard-fought race, while Broc Parkes inherited a surprise third place after Rea's ragged riding caught him out on the final lap when he crashed at Tosa. He would recover to 11th.

Marino completed his best-ever WSS result in fourth place, ahead of David Salom, who too benefits from Davies's failure to score, even if his hopes are even slimmer at 48 points adrift.

A race of high attrition, late crashes for Massimo Roccoli, Alexander Lundh and Ronan Quarmby from top ten positions dented the mid-field, with James Ellison coming through to take a strong sixth, ahead of Vittorio Iannuzzo, Miguel Praia, wild-card rider Stefano Cruciani and Danilo Dell-Omo.

The recovering Rea gets four points for his efforts in 11th, ahead of Pawel Szkopek, Patrik Vostarek, Ondrej Jezek and Imre Toth.