The three-time National League MVP did not play Sunday against the Florida Marlins -- a scheduled day off -- and is not expected to play against the Minnesota Twins on Tuesday, a game also being played in Fort Myers.
"We'll definitely give him tomorrow," said Cardinals manager Tony La Russa. "Even if we were home, I don't think he'd play. We'll see how he feels on Wednesday."
Pujols first experienced discomfort in his back on Sunday. Joe Mather will take his place at first base against the Red Sox.
Cardinals general manager John Mozeliak said he spoke to a trainer at the team's spring training complex in Jupiter and that Pujols is feeling better.
"It's just precautionary because obviously it's a three-hour bus ride over here, and we thought it made more sense to allow him today and see how it feels tomorrow morning," said Mozeliak.
"Obviously you want to be smart. You don't want to take something small and make it big."
Mark McGwire saddened by brother’s betrayal in writing book about steroid usePep defends Henry handling
