Mears (elbow) will begin a rehab assignment at Single-A Bradenton on Wednesday, Jason Mackey of the Pittsburgh Post-Gazette reports.
Mears began the season on the 60-day injured list as he continues to recover from arthroscopic elbow surgery, and his rehab assignment will likely be the final step in his recovery process. The right-hander isn't eligible to be activated until early June, so he'll presumably make several appearances in the minors before rejoining the Pirates' bullpen.