Spain's Dani Pedrosa sealed his third win of the season with an impressive victory in the Indianapolis MotoGP.
Pedrosa, who fell while leading at the Brickyard 12 months ago, started fifth but had moved up to the second by the lap four.
He then got ahead of pole-sitter and home favourite Ben Spies on lap eight before gradually extending his lead.
He finished 3.575 seconds clear of Spies, who earned his best-ever finish, with championship leader Jorge Lorenzo third and Valentino Rossi fourth.
It was Lorenzo's worst result of the season, but he still leads the standings by 68 points from Pedrosa, with seven rounds to go.
"I shouldn't be disappointed with third place but at the same time I'm not happy with my race," Lorenzo said. "I didn't ride as well as I could have and I didn't get a good start."
Pedrosa said: "It was an especially tough one because of the heat.
"I didn't make the perfect start but I was quite quick through the first few tight corners and stayed close to the leaders.
"When I was out in front it was quite hard to stay focused and at the end of the race I was really tired but I'm very happy because last year I crashed when I could have won and now I have made up for it."
World champion Rossi finished fourth, despite crashing in morning practice, and remains fifth overall, one place ahead of Spies.
Pedrosa's other wins this season have come in Italy and Germany.
The next race on the calendar is next Sunday in San Marino.
Earlier, Toni Elias of Spain claimed his third consecutive Moto2 victory in a race that was reduced to just 17 laps following an eight-rider crash on the opening lap.
Pedrosa, who fell while leading at the Brickyard 12 months ago, started fifth but had moved up to the second by the lap four.
He then got ahead of pole-sitter and home favourite Ben Spies on lap eight before gradually extending his lead.
He finished 3.575 seconds clear of Spies, who earned his best-ever finish, with championship leader Jorge Lorenzo third and Valentino Rossi fourth.
It was Lorenzo's worst result of the season, but he still leads the standings by 68 points from Pedrosa, with seven rounds to go.
"I shouldn't be disappointed with third place but at the same time I'm not happy with my race," Lorenzo said. "I didn't ride as well as I could have and I didn't get a good start."
Pedrosa said: "It was an especially tough one because of the heat.
"I didn't make the perfect start but I was quite quick through the first few tight corners and stayed close to the leaders.
"When I was out in front it was quite hard to stay focused and at the end of the race I was really tired but I'm very happy because last year I crashed when I could have won and now I have made up for it."
World champion Rossi finished fourth, despite crashing in morning practice, and remains fifth overall, one place ahead of Spies.
Pedrosa's other wins this season have come in Italy and Germany.
The next race on the calendar is next Sunday in San Marino.
Earlier, Toni Elias of Spain claimed his third consecutive Moto2 victory in a race that was reduced to just 17 laps following an eight-rider crash on the opening lap.