In 2013, Benoit became the closer for the Detroit Tigers. He replaced José Valverde, who accepted an assignment to the Toledo Mud Hens on June 21, 2013 and was subsequently released. Joaquín successfully converted his first 22 save opportunities of the 2013 season, before blowing saves in two of his final four chances, making him 24-of-26 overall. He finished the regular season with a 2.01 ERA and a 1.03 WHIP. In the ALCS against the Boston Red Sox, Benoit gave up a game-tying grand slam home run to David Ortiz, which tied the game at 5. The Red Sox would go on to win the game 6-5, and eventually the series 4-2.