He threw off the mound for the first time since landing on the disabled list in June because of a strained right forearm. His elbow was "barking," according to Phillies pitching coach Rich Dubee. Dubee cut short the session.
Contreras will see a doctor for further evaluation.
Joe Blanton also threw in the bullpen, and Dubee said it went well. There is no timetable for his return, but he has been shooting for sometime in September. Blanton, who has been on the DL since May because of right elbow inflammation, will be pitching out of the bullpen, if he returns.