Carpenter threw 30 pitches during a bullpen session Wednesday as a "pre-game warmup." Carpenter will throw again Saturday and is expected to throw an "extended session." That session will involve Carpenter taking breaks after he pitches to simulate throwing a game. 

Carpenter said he and the team will have a better idea of if and when he'll return by May 28.

Carpenter has been bothered by back and hip issues the last two springs, and he believes those injuries have contributed to his recent shoulder problems. A cortisone shot in his right hip seems to have alleviated his pain, and is the main reason he's ahead of schedule in his rehab. Carpenter said he's working to improve that area. "There is definitely a weakness in my right hip and lower back on that side, and we’re really trying to concentrate on it," Carpenter said.

Carpenter is slated to throw off the mound Monday. The team is hoping to have a throwing schedule planned out by the end of the next homestand. Carpenter was not expected to pitch this year after struggling with a shoulder issue during the spring.