Mahle (hamstring) was reinstated from the 10-day injured list and optioned to Triple-A Louisville on Thursday.
Mahle landed on the IL on July 22 due to a left hamstring strain, though he finished his rehab with Triple-A and will remain with the Bats after being activated. He owns a 4.93 ERA and 1.32 WHIP with a 106:26 K:BB over 102.1 innings this season in the big leagues and figures to resurface in the majors once rosters expand in September.