Chen said he threw all his pitches during the workout.
"I'm a little rusty, but I can make adjustments. I should be OK," he said.
Chen has been out since April 25, and left-hander Danny Duffy has taken over his spot in the starting rotation. As yet, there's been no decision on when Chen might go to the Minors on an injury rehabilitation assignment.
"They don't want to get ahead of themselves," Chen said.
Dick Kaegel is a reporter for MLB.com. Earl Bloom contributed to this report.