MotoGP rookie Marc Marquez overtook title rivals Dani Pedrosa and Jorge Lorenzo to claim his fourth victory of the season at Indianapolis, extending his championship advantage.
Unbeaten throughout practice and qualifying, the 20-year-old lost out to his fellow front row starters into turn one, with Lorenzo taking the early advantage for Yamaha.
The trio soon broke clear of the field, with Marquez taking the runner-up spot from Repsol Honda team-mate Pedrosa on lap 8 of 27.
The reigning Moto2 champion then launched his victory pass at the halfway stage, drifting wide on the exit of the fast left-hand first turn sweep, then outbraking Lorenzo into the following tight right-hander.
The trio spent several more laps together, before Marquez's superior pace began to tell, his lead topping the one-second mark by lap 19. Marquez pulled away to complete a clean sweep of the three US based events, while Lorenzo and Pedrosa - who had both used the summer break to rebuild fitness from collarbone injuries - remained locked in battle.
Pedrosa reclaimed second position by overtaking Lorenzo at the start of the penultimate lap, quickly pulling a buffer over the #99.
Marquez won by 3.495s from Pedrosa, who was 2.2s ahead of Lorenzo.
Marquez has now won more races than any other rider this season, and finished on the rostrum in nine out of the ten rounds. The #93's title advantage stands at 21 points over Pedrosa, with reigning double champion Lorenzo 35 points behind.
The leading trio, like all the factory and satellite riders, opted for the harder front and softer rear tyre compounds.
A closer three-way contest decided fourth position on the final lap, with Valentino Rossi recovering from a season-worst ninth in qualifying to mount a late charge - catching and eventually passing both Cal Crutchlow (Tech 3 Yamaha) and Alvaro Bautista (Gresini Honda), who had battled for much of the race.
Stefan Bradl took a lonely seventh for Honda LCR, while another final turn showdown decided eighth, ninth and tenth: Nicky Hayden bumped past Ducati team-mate Andrea Dovizioso, sending them both over the kerb on the exit - allowing Tech 3 rookie Bradley Smith to blast by the Desmosedicis on the run to the line!