American Nicky Hayden won the Dutch TT on Saturday to go 42 points clear in the MotoGP championship after a dramatic last lap duel with compatriot Colin Edwards.
Yamaha's Edwards, overtaken by his Honda rival on the penultimate lap, seized back the lead but then crashed at the final chicane.
The Texan's exit left Kentucky-born Hayden clear to take the chequered flag and step up to the top of the MotoGP podium for the first time this season, and only the second time in his career.
World champion Valentino Rossi, Edwards's team mate, finished a painful eighth in a damage limitation exercise after breaking a bone in his hand in Thursday's practice and starting at the back of the field.
Edwards, a former world superbike champion, had seized the lead into the first corner and stayed in front until the penultimate lap when he left the door open for Hayden to slip through.
The Texan fought back and recovered the lead only to wobble on the kerb, the crash destroying his hopes of a first MotoGP victory.
The bruised Edwards clambered back on his battered bike and finished 13th as Kawasaki's Japanese rider Shinya Nakano inherited a surprise second place.
Spain's Dani Pedrosa was third for Honda.
Hayden took his points tally to 144 with Pedrosa on 102 and Italian Loris Capirossi, struggling to be competitive after a big crash in Barcelona last weekend, third on 100 points. Rossi slipped from third to fourth with 98.
"It was super-important [to win]," said Hayden in the post-race news conference. "Everyone was telling me be careful, be careful, just get a few points but today the bike was too good and I had to go for the win.
"Colin was really so smooth, so fast out there that I didn't know if I had anything for him. I just couldn't really get close enough and I knew I needed to try and do something different," added the American.
"I changed something on one section of the track that made all the difference in the world and the last few laps I was able to close down on him and get the win."
Australian rookie Casey Stoner was fourth, ahead of Americans Kenny Roberts and John Hopkins, the Suzuki rider who started on pole position for the first time.
With six riders falling at the first corner at the previous Catalan Grand Prix, an accident that kept Ducati's Sete Gibernau out of Saturday's race, the field made a nervous start with Edwards seizing the initiative.
He and Hayden, running close behind, then broke away from the rest and were more than six seconds clear of Nakano with two laps to go.
"I didn't know what was happening on the last lap," said the Japanese after the best result of his MotoGP career. "I just saw some smoke...a yellow bike and then I understand I got second."