Oakland Athletics right-hander Jharel Cotton has been diagnosed with a sprained ulnar collateral ligament in his pitching elbow as well as a strained flexor muscle.
An MRI on Thursday showed the injuries. Cotton will seek a second opinion before deciding whether to have surgery, which would probably sideline him for the season.
"Obviously not great news," Athletics manager Bob Melvin told reporters.
Cotton, 26, started 24 games last season for Oakland, going 9-10 with a 5.58 ERA.
Jharel Cotton seeks second opinion after MRI shows sprained UCL