Halladay declared he was ready to start after throwing a 54-pitch session on Friday. He also threw in the bullpen Tuesday.
Halladay left a June 12 outing against Florida two pitches into the fourth inning due to a sore groin, the only time in 14 starts this season he has not gone at least seven. He felt discomfort after throwing again in Philadelphia last Wednesday and was placed on the disabled list retroactive to June 13.
The Blue Jays optioned left-hander Brad Mills back to Triple-A Las Vegas after Saturday's game. Mills had a 14.09 ERA in two games with Toronto.
The Associated Press contributed to this story.