Darvish will undergo an MRI on his shoulder after leaving his Sunday rehab start after just one inning, Mark Gonzales of the Chicago Tribune reports.

EDGE Analysis

Darvish had made one rehab appearance back in late June but was shut down after experiencing similar discomfort. He hopes that he'll pitch again this season, but that's suddenly a doubt after it looked like he was finally back on the right track. His prognosis should become clearer following the MRI.