Stoner was in scintillating form in Malaysia

He became the first rider to win in all three classes in Sepang.

The 22-year-old Australian won in Sepang in the 125cc race in 2004 and the 250cc race in 2005.

The Ducati rider started second on the grid on Sunday but stormed into the lead on the first lap and stayed there to win by almost two seconds.

Interview: World champion Casey Stoner

Italian Marco Melandri was second with Spaniard Dani Pedrosa third.

Stoner, who clinched his first world title last month in Japan, also equalled Colin Edwards' 2005 record by claiming his 17th finish among the points this season.

"Riding conditions were difficult," he said. "It was also difficult to be in front all by myself."

Malaysian Grand Prix MotoGP result:

1. Casey Stoner (Australia) Ducati 43:04.405
2. Marco Melandri (Italy) Honda 43:06.106
3. Dani Pedrosa (Spain) Honda 43:06.731
4. Randy de Puniet (France) Kawasaki 43:08.170
5. Valentino Rossi (Italy) Yamaha 43:09.178
6. Toni Elias (Spain) Honda 43:22.072
7. Chris Vermeulen (Australia) Suzuki 43:25.355
8. John Hopkins (U.S.) Suzuki 43:26.603
9. Nicky Hayden (U.S.) Honda 43:26.855
10. Colin Edwards (U.S.) Yamaha 43:34.151