Burns, 27, returns to the Storm Chasers after appearing in four games for the Royals since his July 17 callup. He's batting .167 with no extra-base hits through seven games in the big leagues this season.
Chad Thornburg is a reporter for MLB.com based in Los Angeles. This story was not subject to the approval of Major League Baseball or its clubs.
Royals left-hander Jason Vargas is coming off back-to-back disappointing starts -- allowing 12 runs over 7 2/3 innings in those outings, including a 2 2/3-innings performance last time out against the Tigers, his shortest start of the season.