Holderman was forced to exit Thursday's rehab outing with Triple-A Columbus after aggravating his right wrist injury, Tim Stebbins of MLB.com reports.
Holderman was in the final stages of his recovery from right wrist inflammation that caused him to land on the 15-day injured list. However, the 30-year-old relief pitcher has suffered a setback in his rehab program and will undergo more tests to determine next steps.