After a successful minor league career, the 23rd overall pick by the Arizona Diamondbacks was named to the Royals’ 40-man roster in 2017. In his debut season, Peacock pitched for the Hillboro Hops, logging a 2.45 ERA in 22 relief appearances. He then was promoted to the Triple-A Omaha Wingnuts, where he posted a 4.96 ERA over 37 relief appearances. Peacock has three pitches in his arsenal: his sinker, his slider, and his changeup.