Sims, 21, has a 3.00 ERA and 16:7 K:BB ratio through nine innings for Double-A Mississippi.
The former first-rounder has seen an uptick in strikeouts since an abysmal 2014 campaign. Still, control remains a concern, as he walked 54 batters in 92.2 innings last year. Strikeout stuff is difficult to come by, though, so Sims remains a high-risk, high-reward prospect for the Braves.