Royals Opening Day starter Yordano Ventura left Monday's game in the seventh inning after dropping to the ground in obvious pain as he grabbed his right hand.
But the Royals indicated within a few minutes that Ventura had simply experienced a cramp in his right thumb and that they did not consider the injury serious.
"He gets them all the time," manager Ned Yost said.
Ventura was pitching to White Sox cleanup hitter Adam LaRoche after having just given up a homer to Jose Abreu when he threw a pitch that LaRoche fouled back. Ventura suddenly went to the ground, clutching his hand.
"I felt it lock up on me," Ventura said through interpreter Jeremy Guthrie. "I thought at first it was something really bad. I'm happy that it isn't and I'm not concerned about missing any time with what happened. Just a cramp that surprised me, but I feel confident going forward.
"I have had [cramps] before, but never as serious as today. I've pitched through them without letting anybody know that I had them. This one was different."
Ventura gave up one run through six-plus innings and got the victory in the Royals' 10-1 triumph.