Matt Garza’s long road back has taken another detour.

The Cubs scratched Garza from Wednesday’s rehab start at Double-A Tennessee. General manager Jed Hoyer described the issue as the “dead arm” pitchers sometimes experience during spring training, though Garza has been facing questions about his health since last summer.

After Tuesday’s 4-2 win over the Cincinnati Reds at Great American Ball Park, Hoyer gathered the reporters in the clubhouse and indicated “it’s all muscular, nothing structural,” an issue with Garza’s forearm and bicep.

Garza hasn’t pitched in a real game since July 21 last season and was ultimately shut down with a stress reaction in his right elbow.

Hoyer said this “dead arm” isn’t related to last year’s elbow injury. Garza also missed roughly three weeks during the 2011 season while dealing with a bone contusion in his right elbow.

Garza strained a lat muscle on his left side during the team’s first full-squad workout in spring training. He threw a simulated game last week in Milwaukee and had been hoping to rejoin the rotation by the middle of May. It’s getting even more difficult to project a timeline now.