Rossi came into the event needing to finish in front of Stoner to delay the Australian's title celebrations - and charged from seventh at the end of lap one to overtake Stoner and then Marco Melandri for the lead with ten laps remaining. But by then the wet track was almost dry and the top three were forced to join the rest of the field in pitting for their spare bikes.

Stoner and Melandri rejoined in fifth and sixth with Rossi - who stayed out an extra lap - initially back on track in second place, behind only eventual winner Loris Capirossi. However, Rossi was soon struggling to control his M1 and pulled straight back into the pits to have the front of his Fiat Yamaha examined - ending his title hopes. After a quick check, Rossi was waved back out, but again ran wide before limping home in 13th place.

"It's a great pity for us how everything has turned out this weekend, because in the dry we were faster than Stoner and we could have had a good chance," sighed Rossi, who last won the MotoGP title in 2005. "After I passed Melandri [for the lead] I came into the box to change and maybe this was one lap too late, but our strategy was more or less okay because I was able to come back into the race with only Loris in front of me.

"We had an intermediate front tyre, a slick cut which is normal in these situations, but the bike was almost impossible for me to ride and turn and it felt like there was something seriously wrong," he revealed. "I came back in but my mechanics could see there was nothing wrong so I went straight out again, and by then it was too late; the race was over for me and the championship was gone. After four or five laps the tyre began to work better and I was able to keep going to the end, but without this problem it would have been possible for me to be on the podium or even to fight for the win with Loris."

"Our mechanics checked quickly but found everything to be normal, so he went back out onto the track," confirmed team director Davide Brivio. "In reality the problem was with the front tyre, which made his bike unrideable for the first few laps after the change. After he rejoined it took him several laps to 'understand' the front tyre, and then was able to finish the race."

Team-mate Colin Edwards later revealed that he suffered exactly the same problem.

"The front tyre I went back out on, the cut slick, was a disaster and I had no choice but to slow right down while I tried to figure out what on earth was going on," said the Texan, who finished one place behind Rossi in 14th. "Valentino came in because it was such a bad feeling and I nearly did the same thing, but in the end I stayed out and just tip-toed around until I could work out how to kind of ride it."

Yet another tyre related problem was the last thing that Rossi, Yamaha or Michelin needed after a season of difficulties - and with the one tyre brand rule now being considered for 2008 - but Rossi was able to put his disappointment to one side and congratulate Stoner on his title victory.

"Congratulations to Loris but especially to Casey on becoming world champion. I am very flattered that he made a dedication to me on his victory t-shirt, if someone else has to win then I am glad it's one of my fans!" joked Rossi. "He is a great rival and I hope that we can continue this rivalry into the future."

"My congratulations to Stoner for this title, we have a great rival for the future and we hope that next year will be very exciting," echoed Brivio.