Boston Red Sox pitcher Chris Sale apologized on Thursday for the way he acted following his rehab start the night before — sort of.

Sale is working his way back from a February rib injury that has prevented him from pitching in the big leagues this season. He pitched 3.2 innings for the Triple-A Worcester Red Sox in a 4-2 loss, and he was not happy with his performance. After he gave up a bases-loaded walk and was pulled, the left-hander took out his frustrations on a TV screen in the tunnel.

Sale told reporters on Thursday that he “acted like an idiot.” He said he does not regret his reaction, however.