Rodriguez (elbow) will begin a rehabilitation assignment at Double-A Frisco on Tuesday, Evan Grant of The Dallas Morning News reports.
Rodriguez has been dealing with inflammation in his elbow since spring training, which eventually landed him on the 60-day disabled list. The Rangers' bullpen ranks sixth in innings pitched (107.0) and 20th in ERA (4.46), so there could be a need for Rodriguez, who got a taste of the majors last season, when he's ready to come of the DL. He's not eligible to be activated until later in May.