Dixon won Dual 2 of the Chevrolet Detroit Grand Prix IndyCar race on Belle Isle in Detroit on Sunday.
Scott Dixon of New Zealand finished with a total time of 1:52:18.93, nearly 2 seconds in front of second place winner Marcus Ericsson of Sweden. Ericsson finished second in the second race with a total time of 1:52:20.87 and Australian Will Power finished third at 1:52:22.59.
It was the third Detroit win for the 38-year-old who won in 2018 and the 45th win of his career.
Josef Newgarden won the first race on Saturday.