Casey Stoner clinched his first world championship title here Sunday with the worst result of his brilliant season at the rain-hampered Japanese Moto GP. The 21-year-old Australian finished only sixth in the race won by Italian and fellow Ducati rider Loris Capirossi for his third straight Japanese Grand Prix victory.
But, with eight wins already under his belt this season, Stoner just needed to finish ahead of Italian ace and archrival Valentino Rossi here to take an unbeatable lead with three races left in the season.
Rossi, five-times world champion in the premier class, slowed down with a tyre problem on his Yamaha on the 24-lap race when he was battling to overtake Capirossi on a drying track to finish 13th.
The result leaves the points gap between the rivals wider at 83, with 25 points for a win. "There is really no better feeling than this," said Stoner.
"I didn't really expect to clinch the title this weekend. It would have been a dream to win the title at any of the remaining races but to do it with three races to go is unreal," he said.
The next race will be held on the Australian's home track of Phillip Island in three weeks. "When I get there, it's gonna be a lot of fun ... I'm gonna be a lot more relaxed," said Stoner.
"I really want to try my best to win my home race," he said. "It's the next focus of my whole season."
Stoner took just two years to become champion, after an erratic rookie year with a one-bike Honda team when he crashed many times and became known as the "crash king."
It was the first drivers championship win for Ducati since the Italian constructors rejoined the purpose-built motorcycle circuit in 2003 after a 30-year break, while dominating the World Superbike event.
After Sunday's race, Ducati have also moved within an ace of lifting their first-ever constructors title of any category, leading Honda by 69 points.
Stoner was the first Australian to win the premier title since Mick Doohan reigned supreme from 1994-1998. Wayne Gardner also triumphed in 1987.
"They've been my heros. I've grown up watching them. Watching them has basically made me into what I am today," said the baby-faced Stoner, who moved with his family to England at the age of 14 - the legal age for racing in England against 16 in Australia.
Capirossi, a 34-year-old veteran, won Sunday's race in 47 minutes 05.484 seconds for his first win of the season. He finished 10.853 seconds ahead of Randy De Puniet of France on a Kawasaki. Toni Elias of Spain was third. After starting from ninth position on the grid, Stoner surged upfront on the fifth lap but gradually slipped back.
Rossi, who has won four races this season, jumped to the lead on the 14th lap and pitted with nine to go. He returned to the track in second spot, some six seconds behind Capirossi, but made another pit-stop again after the next lap. His bike slid off course and almost out of contention.
"In the dry, we were faster than Stoner and we could have had a good chance," said the 28-year-old Italian, adding there was "something seriously wrong" with his front tyre.
"I came back in but my mechanics could see nothing wrong so I went straight out again, and then it was too late," he said. "It's a great pity for us." Stoner became the second youngest rider to conquer the premier GP class at the age of 21 years and 342 days. American Freddie Spencer was 84 days younger when he clinched the title-then 500cc-in 1983.