Jorge Lorenzo's chances of winning the 2009 MotoGP World Championship officially came to an end in the Sepang rain on Sunday, despite mounting a daring last-to-fourth charge in the Malaysian Grand Prix.

Lorenzo had qualified second on the grid, behind only Fiat Yamaha team-mate and title rival Valentino Rossi, but his race bike failed to fire in the pits and he had to switch to his spare machine - a delay that meant he left the pit lane later than planned.

To help gauge the tricky track conditions, after a tropical storm had soaked the circuit, Lorenzo - like Rossi - planned to do two sighting laps. But by the time he came through for the second one the pit lane had closed, meaning he then had to start from the back of the grid.

However the 22-year-old bolted off the line, then surged through the spray to sit eleventh after the first turns - and had overtaken Rossi, who outbraked himself at turn one, on his way to eighth by the end of the opening lap!

Lorenzo and Rossi then began moving up the order together, sitting fourth and fifth by lap seven of 21.

Rossi, who only needed fourth place to clinch his seventh MotoGP title even if Lorenzo won, overtook the #99 on the following lap - and both were later promoted one position by an accident for Andrea Dovizioso.

Fourth for Lorenzo marked the first time this season that he has taken the chequered flag without a podium finish, but under the circumstances he was satisfied with the result - and was among the first to congratulate Rossi on track and in parc ferme.

"I want to start by giving my congratulations to Valentino and all his team. He is the champion,” said Lorenzo, nearing the end of only his second MotoGP season.

“I was hoping to have a good race, but when it started to rain we had problems to turn on the bike,” he said of his penalty. “We had planned to ride two laps, but I didn't have enough time and the pit-lane was closed.

“I had to begin from last position, but I did one of my best ever starts! The first corner was incredible, but as time went on I began to have some grip problems, like during the whole weekend.