Coming into the 1986 season, Sutton had 295 career victories. He struggled early in the season, but earned his 300th career win on June 18, pitching a complete game against the Texas Rangers in which he allowed only three hits and one run while striking out Gary Ward for the final out of the game. He appeared in two games in the 1986 ALCS against the Boston Red Sox, earning a 1.86 ERA but registering two no-decisions.