SAN DIEGO --Padresstarter Jarred Cosart left Wednesday night's game against the Boston Red Sox in the fourth inning after straining his right hamstring and groin.
"Not really sure which one is worse right now," Padres manager Andy Green said after his team's 7-2 loss.
Cosart landed awkwardly after leaping to catchWil Myers' erratic throwwhile covering first base on Jackie Bradley Jr.'s grounder.
Carlos Villanueva relieved Cosart with the game tied 2-2.
"It's pretty cool to go out there and face those guys; it's a playoff team,'' Cosart said of the Red Sox, whose three-run fourth inning proved the difference in the game. "I was holding my own against one of the best pitchers in baseball and was finally getting in a good rhythm, and I just hit a bump in the road."
The Associated Press contributed to this report.