Josef Newgarden won the race.
Three quarters of the way into the race, Rosenqvist crashed when the rear end of the car gave way and he backed into the barrier, but with only damage to the car.
Indycar series leader Marcus Ericsson was well at the top for a long time as second and third, but then he lost position after position and was finally one lap behind the winner in eighth place.
Ericsson remains in the championship lead, but the lead has shrunk to 15 points ahead of Newgarden. He and Rosenqvist get another chance on Sunday when a new race is run in Iowa.