Pirates' Robert Stephenson: Beginning rehab assignment

Stephenson (elbow) is set to begin a minor-league rehab assignment Friday with Triple-A Indianapolis, Justice delos Santos of MLB.com reports.

Stephenson was placed on the 15-day injured list Opening Day, retroactive to March 27, after being slowed this spring by lingering right elbow soreness. He appears to be on track to join the Pirates' bullpen as soon as he is first eligible for activation.