Pittsburgh Pirates starter Chris Archer was lifted between the first and second inning during Tuesday's game against the Washington Nationals after an errant warmup pitch seemed to bother the right-hander.
The team later announced Archer was removed with right shoulder discomfort. He'll have an MRI and be examined by a doctor Wednesday.
"Obviously, it was fine the first inning the way he threw the ball and cut them up, and then something just reacted wrong in his warmups," Pirates manager Clint Hurdle said, according to MLB.com's Alan Saunders. "His warmups were all out of whack. You kind of think, 'That's different.' He knew that it was way too different."
Clay Holmes came in to replace Archer to begin the second frame.
Archer, 30, is in the midst of his first full season with the Pirates since being acquired from the Tampa Bay Rays last season. He's posted a 5.19 ERA and 5.02 FIP in 119 2/3 innings over 23 starts.
Since breaking into the majors in 2012, Archer has been one of the healthiest pitchers in baseball, reaching the 200-inning plateau in three straight seasons between 2015-17. Last season, however, Archer missed time with a left abdominal strain, holding him to 148 1/3 innings over 27 starts between the Pirates and Rays.
Pittsburgh currently sits in fifth place in the division, 15 1/2 games back of the first-place St. Louis Cardinals. The team already lost ace Jameson Taillon earlier this season, who recently underwent Tommy John surgery.