General manager Ruben Amaro Jr. said the results of Monday's exam were "more positive" than the first one on the 39-year-old right-hander in San Diego.
Contreras had been closing for Brad Lidge, who has been out since spring training with a strained rotator cuff and hopes to be back after the All-Star break.
Contreras, who had five saves in five tries and had not allowed a run in eight innings this season. Ryan Madson has taken over since Contreras was hurt.
Philadelphia purchased the contract of right-hander Michael Stutes from Triple-A Lehigh Valley.
