Crain threw 20 pitches in a minor-league game without any setbacks.
"He looked good today," manager Robin Ventura said. "He looked fine and felt fine afterward."
Crain has not pitched in a Cactus League game since incurring the injury March 7. The plan is for Crain to throw three more times before Opening Day in preparation to get back into the bullpen rotation.
"I have been around long enough to know you don't want to push it and jeopardize the rest of the season," Crain said after his morning performance. "I was trying to let it go today. I went straight out there and let it go. I threw all my pitches and felt fine afterwards."
Crain will throw again Monday. He has been the primary setup man from the right side for Chicago since signing a three-year contract before the 2011 season. Teammate Nate Jones is pushing Crain for the setup role this season.
"These are small steps that you take," Ventura said. "You just want to make sure he is out of the woods. If he is healthy he is the first one you want to go to."