FORT MYERS, Fla. -- Twins closer Joe Nathan threw a bullpen session on Tuesday and reported afterward that his right shoulder felt great.

Nathan had been expected to pitch for Team USA in the World Baseball Classic, but pulled out of the event on Sunday due to soreness in the AC joint -- where the clavicle meets the acromion process of the scapula at the top of the shoulder.

The closer threw 40-plus pitches during his session on Tuesday without any pain or soreness in the joint.

The plan now is to have Nathan throw to live batting practice on Thursday and to possibly pitch in the Twins' Grapefruit League contest against the Pirates on Saturday.

Twins manager Ron Gardenhire said that he's not concerned about his closer.

"The only thing you have to do with Nathan is calm him down and make him slow down everything," Gardenhire said. "We told him this is something you can't force the issue with ... But the trainers and doctors told me everything is good. He's going to be fine."