Karstens (shoulder) announced his retirement from professional baseball Sunday on his personal Twitter account. The 32-year-old was forced to shut down his career after requiring surgery on the labrum and rotator cuff of his right shoulder in 2013. Karstens spent seven seasons in the big leagues with the Yankees and Pirates, accruing a 26-40 record, 4.44 ERA, and 1.33 WHIP over 592 career innings.