Shohei Ohtani expressed discomfort in his throwing arm after another abbreviated start on Sunday and was sent for an MRI.
The Los Angeles Angels were still awaiting the results moments after their 6-5, 11-inning loss to the Houston Astros.
Ohtani failed to record an out in his first start since returning from Tommy John surgery last Sunday and couldn't get out of the second inning seven days later.
Ohtani showed good stuff in the top of the first, striking out George Springer with a splitter in the dirt and throwing his fastball constantly in the mid-90s.