On May 15, 1986, King played in his first MLB game. He pitched scoreless innings of relief against the Texas Rangers, posting three walks and three strikeouts, while surrendering only one hit as the Tigers lost by an 8–1 score. For the season, King appeared in 33 games and innings. He started 16, but he also finished 9, recording three saves and three complete games, including one shutout. He tallied an 11–4 record and a 3.51 ERA while striking out 79 opponents and walking 63.