Chicago White Sox right-hander Jake Peavy was scratched from his start against the Texas Rangers on Thursday night because of back spasms.
Peavy said his back locked up on him when he was reaching for his glove after stretching exercises before Wednesday's game. He received treatment throughout the night and was in the training room most of the afternoon Thursday hoping to make the start.
''I've never had anything like this happen,'' the 31-year-old Peavy said. ''I begged and begged to see if we could give it as much time as we could for today. We really haven't put a game plan together other than today just knowing that I can't go.''
Peavy was replaced by Hector Santiago, who was supposed to start Friday in Kansas City with Gavin Floyd on the disabled list with a flexor muscle strain in his right arm.
Manager Robin Ventura said Dylan Axelrod was the likely starter against the Royals since it would be normal rest for the right-hander. Ventura said he didn't think Peavy would be available before Saturday.
''I don't know if he slept on it wrong,'' Ventura said. ''It's not anything that should be longer than just missing a few days.''
Peavy is 3-1 with a 3.38 ERA and tied for the team lead in wins with Chris Sale, who beat Texas on Wednesday night. Peavy has 39 strikeouts in 32 innings.
Peavy missed half of the 2010 season after right shoulder surgery but hasn't been on the disabled list since June 2011.
Santiago is 0-1 with a 2.51 ERA in seven relief appearances this season. He made four starts last year.
Peavy's problem came two days outfielder Jordan Danks was a late scratch because of swelling in his right knee. Ventura said Floyd, who had two stints on the disabled list with elbow problems last year, was seeking multiple opinions on his injury.
Floyd and left-handed starter John Danks (left shoulder) are among six players on the disabled list, including everyday players Gordon Beckham and Dayan Viciedo.
''I think every day you go through the list and figure out who's available, and the training room's full,'' Ventura said. ''It's just part of the playing the game. You just deal with it.''