Cardinals catcher Yadier Molina had to leave Tuesday's game at Cleveland in the ninth inning because of stiffness in his upper back, manager Mike Matheny said.
Tony Cruz batted for Molina and caught the bottom of the ninth in the Cardinals' 8-3 win.
"Yadi tightened up a little bit," Matheny told MLB.com. "I don't know if it was the cold or what it was exactly, so we'll have to keep an eye on him."
Molina, who slid into home for a second-inning run, has never missed significant time during his career because of a back injury.