Mesa Solar Sox
In 2014, Covey began the year with Beloit, before he was promoted to the Stockton Ports of the Class A-Advanced California League. In 26 games (25 starts) between the two teams, he was 7–14 with a 5.46 ERA. He pitched for Stockton in 2015, compiling an 8–9 record with a 3.59 ERA in 26 games started. Covey began the 2016 season with the Midland RockHounds of the Class AA Texas League, but suffered an oblique muscle strain in May and missed the remainder of the regular season. In six starts prior to his injury, he was 2–1 with a 1.84 ERA. The Athletics assigned Covey to the Mesa Solar Sox of the Arizona Fall League.