Campau was also a player and sometimes a manager in minor league baseball for 19 years, including stints with the New Orleans Pelicans (1887, 1892–94, 1903), Kansas City Blues (1888, 1896, 1898), Detroit Tigers/Wolverines (1889–90, 1894–95), Seattle Yannigans/Rainmakers (1896), Grand Rapids Bob-o-links (1897), Rochester Bronchos (1899–1900), and Binghamton Bingoes (1901, 1903–05). Although minor league records from the 1880s and 1890s are incomplete, Campau is known to have tallied at least 2,115 hits, 1,305 runs, 597 stolen bases, 157 triples, and 125 home runs in his minor league career.