Denny Hamlin has won a NASCAR Sprint Cup race for the first time this year, holding off Matt Kenseth at Michigan International Speedway.
The drivers appeared headed for a fuel-mileage finish Sunday.
Then a late caution enabled them to make pit stops before a frantic five-lap sprint to the finish.
Kenseth was the only person with a shot to catch Hamlin in the final moments.
He tried to go both above and below the leader but was unable to pass.
Kyle Busch finished third, giving Joe Gibbs Racing a 1-3 finish after the team was told to change oil pans before Friday's practice.
NASCAR said oil pans from cars driven by Hamlin, Busch and Joey Logano were not submitted for approval before opening day inspection.