Ben Spies capitalised on Marco Simoncelli's early crash to cruise to his maiden victory in the Dutch MotoGP.

In damp and overcast conditions in Assen, Simoncelli squandered his pole position on the first lap after a clumsy clash with Jorge Lorenzo.

Both came off before continuing, but it allowed the American to build a lead which he held for a long-awaited win.

Championship leader Casey Stoner finished second to extend his lead to 28 points at the top of the standings.

Honda's Andrea Dovizioso took third place, ahead of Ducati's seven-time world champion Valentino Rossi, who has finished on the podium just once this season.

The race's key moment came just three corners in when Simoncelli and Lorenzo collided after the Italian lost grip of his bike and wiped the defending champion off the track.

That played into Spies's hands, who becomes the first former World Superbike rider to win a MotoGP race since Troy Bayliss in 2006.

"I could see on the big screen what had happened on the first lap [the Simoncelli and Lorenzo collision]," Spies told BBC Sport.

"I had a really good feeling on the warm up lap, so I wanted to go out as hard as I could at the beginning. Once I saw I had a gap I tried to keep the gap between Casey and I at three to four seconds.

"Each time he got closer I put in a big lap.

"To do it in front of the Assen fans on Yamaha's 50th anniversary was great," Spies added.

But it turned out to be a very satisfactory afternoon for Stoner, who remains in charge at the top of the overall standings.

"We were a bit disappointed we didn't get to test our settings in the warm-up but Ben just had a pace that I couldn't match," said Stoner. "Once Ben got that gap I couldn't bring it back.

"But I am very happy with the result, especially with how things have gone this weekend," Stoner added.

Assen MotoGP result:
1. Ben Spies (US) Yamaha
2. Casey Stoner (Aus) Honda
3. Andrea Dovizioso (Ita) Honda
4. Valentino Rossi (Ita) Ducati
5. Nicky Hayden (US) Ducati
6. Jorge Lorenzo (Spa) Yamaha
7. Colin Edwards (US) Yamaha
8. Hiroshi Aoyama (Jpn) Honda
9. Marco Simoncelli (Ita) Honda
10. Toni Elias (Spa) Honda

Championship standings:
1. Casey Stoner (Aus) Honda 136 pts
2. Jorge Lorenzo (Spa) Yamaha 108
3. Andrea Dovizioso (Ita) Honda 99
4. Valentino Rossi (Ita) Ducati 81
5. Nicky Hayden (US) Ducati 71
6. Dani Pedrosa (Spa) Honda 61
7. Ben Spies (US) Yamaha 61
8. Hiroshi Aoyama (Jpn) Honda 51
9. Colin Edwards (US) Yamaha 46
10. Marco Simoncelli (Ita) Honda 39

BBC Sport