Lorenzo came into the race holding a perfect podium record and the joint world championship lead, but had badly injured his ankles during a huge Friday highside - then stalled on the grid as the formation lap began.
The
MotoGP rookie attempted to re-fire his Fiat Yamaha with a bump start, doing little to reduce the pain from his injured ankles, before getting assistance from officials and taking his fourth place on the grid.
The Spaniard, who celebrated his 21st birthday today, looked understandably cautious in the early stages - and had been mercilessly pushed back to eighth by the halfway mark - but retaliated with a combative performance during the last ten laps to pull a comfortable 4.4secs clear of fifth place.
The tailwind on the back straight contributed to a multitude of braking mistakes into the ultra-tight hairpin, with pole sitter
Colin Edwards one of the most high profile victims.
The Texan swapped the lead with Stoner during the opening laps but - having been passed by Rossi and Pedrosa - had looked more than capable of holding third, until he ran wide on lap 6.
That dropped the Tech 3 Yamaha rider to seventh, where he eventually finished - in the middle of a close five-man pack - behind
Marco Melandri and
Nicky Hayden, and ahead of
Toni Elias and
Loris Capirossi.
Melandri delivered by far his best race of the season, the Italian looking like a man transformed as he charged from 12th on the grid to fifth, shattering his previous best race finish of eleventh and releasing some of the huge pressure on his shoulders after a nightmare start to his Desmosedici career.
Capirossi was the only Rizla Suzuki rider to reach the flag after
Chris Vermeulen retired with chain problems, whilst
James Toseland endured his toughest MotoGP race yet - crossing the line in twelfth, albeit just a fraction behind fellow rookie
Andrea Dovizioso, who faded backwards in the closing stages.
