Moustakas was optioned to Triple-A Omaha Thursday morning, and Kansas City recalled Jimmy Paredes to fill the roster spot.
Through 40 games this season, Moustakas -- a former first round draft pick -- was batting just .152 with four home runs and 17 RBI. Since breaking into the league with 89 games in 2011, his numbers have steadily dropped. Moustakas on-base percentage as a rookie was .309 and decreased since to .296 in 2012, .287 in 2013 and finally .223 this season.
Danny Valencia will take over duties at third base, with Paredes also getting some innings on the left side of the infield.