Dani Pedrosa claimed his second victory of the season as the Spaniard won the Indianapolis MotoGP in emphatic fashion.
The Honda driver led a Spanish one-two, finishing 11 seconds ahead of compatriot Jorge Lorenzo while Italy's Andrea Dovizioso completed the podium.
Australian world champion Casey Stoner, riding with a pain-killing injection due to his fractured right ankle and torn ligaments, finished fourth.
It was Pedrosa's 17th career victory and puts him on 207 points in the world championship standings, 18 points behind Lorenzo.
"Well I had to keep, I had to keep the concentration. Then I see, I was leading and when I see this oil, let's say, from Ben I was in to turn 1 and didn't know really where to go for a couple of laps. And the I had a mistake in turn 2 but able to stay on two wheels and keep the rhythm until the end," he said after the race.
Marc Márquez (Team CatalunyaCaixa Repsol) recorded an easy victory in the Moto2 race in front of Pol Espargaró and Julian Simón and in doing so extended his championship lead.
With 11 laps to go Marquez had a lead of six seconds and never looked back to take the trophy and move 39 points clear of Pol Espargaro (Spain) Kalex in the standings.
In a drama filled Moto3 race RW Racing GP's Luis Salom claimed his first-ever victory ahead of Sandro Cortese (Germany) and Jonas Folger, with Maverick Viñales crashing out on the final turn.
Cortese, Viñales and Salom swapped positions on the final lap but the latter was able to squeeze out a thrilling win.
Cortese now has a 29-point lead at the top of the championship over Maverick Vinales (Spain) Honda and Slalom.
Reuters