Stewart (groin) caught off a pitching machine Monday, the Pittsburgh Post-Gazette's Bill Brink reports.

EDGE Analysis

Stewart has been dealing with left groin discomfort since Friday. However, an MRI came back negative Saturday, as he hopes this step in his rehab process keeps him on track to be available for Opening Day, although Francisco Cervelli is expected to carry a heavy bulk of the catching duties this season. The 35-year-old says he felt fine after catching the machine, but did not really test himself, so his status will remain uncertain until he does.