The Braves optioned Sims to Triple-A Gwinnett after Monday's game, according to 680 The Fan.
Sims was just called up over the weekend, but he will be replaced by a fresh arm in Matt Wisler after being tagged for two earned runs while throwing an inning in Monday's contest. Sims has been shuffled between Triple-A and the majors all season, so he will likely be back with the big club again at some point this summer.