Keselowski, the pole-sitter, had led for 131 laps until Harvick grabbed the top spot just after a restart with 45 laps remaining.
But Keselowski passed Harvick with 21 laps to go after the Richard Childress Racing competitor got stuck behind behind the lapped car of Amber Cope, beating him at the finish by 0.7 seconds.
After the race, Harvick bumped the front end of Cope's car to register his displeasure.
Stenhouse collapsed from heat exhaustion after climbing out of his car on pit road following the conclusion of the race. He was taken to the infield medical care center where he was said to be awake and alert.