Duffy didn't play after June 27 because of a badly sprained left ankle. He had nearly recovered from that problem in late August when pain in his left shoulder prompted surgery to repair damage in his labrum and rotator cuff.
Before getting hurt, Duffy hit .249 with three homers and 22 RBIs in 70 games.
Duffy is one of only two non-catching position players attending a Pirates pitching minicamp in Bradenton, Fla., this week. Outfielder Kevin Thompson is recovering from a right shoulder injury.