Unlike many Negro League players who flitted from team to team, Harris spent most of his career (23 of 28 years) with one club – the Homestead Grays – as a strong-hitting outfielder and manager. He started playing as a 17-year-old with the Cleveland Tate Stars, and settled in with the Grays during their strong independent years. He was an aggressive baserunner and could “undress an infielder, cut the uniform right off his back,” according to one contemporary.
Harris managed the Grays during their years in league play, from 1936 through 1948, winning nine consecutive pennants (1937-45) and two Black World Series titles (1943 and 1944). In 1938, when the Grays dominated the league and won the first half with an .813 winning percentage, Harris reportedly hit .380. In the waning days of the Negro Leagues, he coached for the Baltimore Elite Giants in 1949 and managed the Birmingham Black Barons in 1950.