Rea was recalled from the Cubs' alternate camp site Thursday, Patrick Mooney of The Athletic reports.
Rea will replace Dillon Maples on the roster and in the bullpen. The right-hander spent all of last season with Triple-A Iowa, posting a 3.95 ERA and 1.36 WHIP across 26 starts (148 innings). He'll likely provide length out of the bullpen for the Cubs.