Contreras went 7–2 and posted a 3.30 ERA, but he spent two months on the disabled list with a subscapularis strain, had four stops in the minor leagues, and was in and out of the bullpen. While a starter, Contreras was 6–1 with a 2.34 ERA. Out of the bullpen he was 1–1 with a 7.43 ERA. His best game occurred on September 23 at U.S. Cellular Field, in which he shut out the White Sox for eight innings while striking out nine. Contreras appeared in the 8 postseason games, pitching 11 innings total, with a 5.73 ERA striking out 17.