The move makes room for Saturday's starter, Felipe Paulino, who is returning from the disabled list.
In seven relief appearances with the Royals this season, Coleman posted a 4.15 ERA. He allowed four runs on eight hits, four walks and a pair of home runs in 8 2/3 innings pitched.
Vinnie Duber is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.