Gordon banged his head against a post in the bullpen fence as his backside hit the warning track as he tumbled backward in a vain attempt to catch a fly ball in the sixth inning of Wednesday night's game against Cleveland at Kauffman Stadium.
Tests determined that Gordon had not suffered a concussion as feared, but his hindquarters were badly bruised.
He was in the Royals' dugout in both games since and had his batting gloves on during a ninth-inning rally in Friday night's 6-3 loss to the A's.
"We had him ready to hit last night if it got to [Johnny] Giavotella with a chance to win it," Yost said. "I needed [Lorenzo] Cain or [Mike] Moustakas to get on to put us in that position but it didn't happen."