Cahill's absence leaves Monday's starter against the Rockies as a question mark. The Padres recalled right-hander Zach Lee from Triple-A El Paso. Lee hasn't pitched yet this season, so he'd certainly be available. So is right-hander Jarred Cosart, who lost out in a rotation battle with Cahill this spring. Cosart has been serving in the bullpen.
The Padres signed Cahill to a one-year deal during the offseason. He had spent most of the previous two seasons pitching in relief for the Cubs. Wednesday's 99-pitch outing was his longest since August 2014.
Cosart seems the likeliest option to replace Cahill, should the injury linger.