Sims was recalled from Triple-A Louisville on Thursday.
Sims figures to provide bullpen depth for the Reds while David Hernandez (shoulder) is on the mend. The right-hander has worked strictly as a starter this season, so he should offer length out of the bullpen. Prior to earning a promotion, Sims compiled a 4.56 ERA, 1.33 WHIP and 102:36 K:BB in 16 starts for Louisville.