 Miller began the 2012 season in the minors while recovering from an injury.When he was called up to the majors, the Red Sox moved him to the bullpen, which became permanent after having posted a 5.70 ERA in 66 career starts.Miller limited left-handed batters (LHB) to a .149 average (13-for-87) in 2012, the second-lowest in the AL for all pitchers with a minimum of 100 batters faced, and the lowest average by a Red Sox left-handed pitcher since at least 1974.