He played in Major League Baseball (MLB) for the Kansas City Royals, Texas Rangers, and Cincinnati Reds.

[1] On July 29, 2009, he was traded with Ronny Cedeño, Jeff Clement, Aaron Pribanic, and Brett Lorin to the Pittsburgh Pirates in exchange for Ian Snell and Jack Wilson.

[3] On June 13, 2013, the Arizona Diamondbacks claimed Adcock off of waivers and assigned him to the Reno Aces of the Triple–A Pacific Coast League.

On July 31, 2015, it was discovered by doctors that Adcock sustained a tear in his ulnar collateral and would need Tommy John surgery, ending his season.

His sinker was thrown in the low 90s and had superb movement; it averaged nearly a foot of tailslide break away from left-handers and in toward right-handers.