Detroit Tigers left-hander Matthew Boyd realized something was wrong with his body and signaled to manager AJ Hinch in the dugout.
Moments later, Boyd walked off the mound and into the clubhouse with athletic trainer Doug Teter. He was removed from Monday's game against the Kansas City Royals in the third inning with left arm discomfort. The Tigers, with a 4-0 lead, turned to righty reliever Joe Jimenez.
In the fifth inning, right-handed reliever Alex Lange left with an apparent injury.
Boyd, who is undergoing further evaluation, threw 41 pitches, 29 for strikes.