Four-time world MotoGP champion Valentino Rossi [Images] ended Australian Casey Stoner's winning streak on Sunday with victory at the US MotoGP.

Rossi, who also has world titles in the 500cc, 250cc and 125cc classes, negotiated the 32-lap race in 44 minutes 4.311 seconds and at an average speed of 157.270 kph (97.71 mph).

The Italian took advantage of Stoner's mistake when the Australian rode into the gravel on lap 24 to claim his fourth win of the season, but first of his career in the US.

"I was fast all week and I had a great start and was very good with my braking," said Rossi. "It was an important win for me since it was my first in America."

Stoner, the reigning world champion who claimed the last three MotoGP races and five consecutive poles, trailed Rossi by 13 seconds. Chris Vermeulen of Australia was third, 26 seconds behind Rossi.

Following the first-lap crash of Spain's Jorge Lorenzo, Rossi and Stoner emerged at the front of the field and steadily pulled away. The two riders exchanged leads several times for more than half of the race.

"I had to stay in front, because it's a hard course to overtake riders," said Rossi. "I got 25 points (for the win) and now I can relax a little bit for going on a holiday. But we have a lot of work to do. There are seven races left."

Stoner, who fell off his bike after riding into the gravel, admitted he had made the mistake after an exciting series of passing manoeuvres with Rossi.

"I made a little mistake; it was my fault," said Stoner.

"I'm a little disappointed, but I am still happy with the performance. It was some of the most aggressive moves I've ever been in. They were good, clean moves."

Rossi's win extended his overall standings lead to 212 points with seven of 18 events left. Stoner is second with 187 points.

Dani Pedrosa of Spain is third with 171 points.

Pedrosa rode in practice sessions, but did not attempt to qualify on Saturday because of lingering left hand and wrist injuries suffered last week in Germany [Images].