Helped by a nightmare opening lap for Ben Spies, Casey Stoner cruised to his 30th MotoGP victory in Sunday's Indianapolis Grand Prix.

The Repsol Honda star dropped from pole to third on lap one - behind team-mate Dani Pedrosa and title rival Jorge Lorenzo - but that was nothing compared with the first-lap misery for Spies.

The only rider that looked capable of seriously challenging Stoner, Spies dropped from second to fifth off the line, was shuffled further back through the opening turns, then clipped the back of Dovizioso - leaving him ninth at the end of the lap.

Stoner went on to slipstream past Lorenzo's Yamaha along the home straight at the start of lap two, then repeated the pass to take the lead from Pedrosa on lap 7 of 26.

The Australian soon put several seconds between himself and Pedrosa, then monitored his advantage to the finish, aware of tyre endurance fears on the new, abrasive, asphalt.

Stoner, who had never previously finished on the podium at Indy, won his seventh race of the season by 4.828sec from Pedrosa.

Spies had fought his way up to fourth by the halfway stage, then passed team-mate Lorenzo for third at the start of lap 18, when he was the fastest rider on track.

But Pedrosa was already long gone and the Assen winner had to be content with the final place on his home podium.

Reigning world champion Lorenzo came under late pressure from Dovizioso for fourth and has now dropped from 32 to 44 points behind Stoner, with six rounds remaining.

While the frontrunners didn't seem to suffer any major tyre problems, there were some high-profile casualties - and plenty of 'marbles' offline.

Nicky Hayden's first race on the GP11.1 saw the American burst from eighth to fourth on the opening lap, but he was the only rider to choose the softer-option front and was ultimately forced to pit in the closing stages.

Gresini Honda's Marco Simoncelli likewise slipped from fifth in the early stages to twelfth at the flag, while fellow Italian Valentino Rossi had a strange race.

The seven-time world champion - who had qualified just 14th after a crash in qualifying - ran tenth in the early stages, was then passed by Hector Barbera, and looked on the verge of retirement as he dropped to last place.

But the Italian recovered to claim tenth at the chequered flag, in a race where only satellite Ducati riders Barbera, Karel Abraham and Loris Capirossi failed to finish.

Barbera crashed at the final turn, on the final lap, while trying to pass Aoyama for ninth, while Abraham and Capirossi pulled into the pits.

Alvaro Bautista claimed a solid sixth for Suzuki, with Monster Yamaha Tech 3's Colin Edwards the leading satellite rider, in front of his home fans, in seventh.

Pramac's Randy de Puniet and Gresini's Aoyama separated Edwards and Rossi, with rookie Cal Crutchlow 1.8sec behind The Doctor.

The San Marino Grand Prix takes place at Misano next weekend.

Indianapolis Grand Prix:

1. Stoner
2. Pedrosa
3. Spies
4. Lorenzo
5. Dovizioso
6. Bautista
7. Edwards
8. de Puniet
9. Aoyama
10. Rossi
11. Crutchlow
12. Simoncelli
13. Elias
14. Hayden