Buehrle began the 2015 season as the fourth starter in the Blue Jays rotation. In his first start of the season, he defeated the Baltimore Orioles 12–5 and earned the 200th win of his career, joining Bartolo Colón, Tim Hudson, and CC Sabathia as the only active pitchers with at least 200 wins. He also became the second pitcher to record his 200th win in a Blue Jays uniform, joining Roger Clemens. On May 29, Buehrle threw his first complete game of the 2015 season, defeating the Minnesota Twins 6–4. In his next start, Buehrle pitched his tenth career complete game shutout, needing only 93 pitches to defeat the Washington Nationals 8–0. He earned his 30th career win against the Minnesota Twins on August 6, becoming the 21st pitcher to have 30 or more wins against one franchise since 1961. Buehrle made what many believed to be his final appearance of the season on October 2, holding the Tampa Bay Rays to 4 runs over 6 innings and earning his 15th win. The start left him two innings short of continuing his streak of 14 seasons with 200 or more innings pitched. On October 3, it was reported that Buehrle would attempt to throw the two innings the following day, and would retire afterward, as he did not believe he would be included on the postseason roster. In the subsequent game, Buehrle was only able to pitch of an inning, after errors in the field resulted in Tampa Bay scoring eight unearned runs on five hits. After the game Buehrle, confirmed that he was not named to the Blue Jays' post-season roster, but that he had not yet made a decision about playing the next season.