The Cardinals first baseman aggravated a strained left calf during the seventh inning of a 7-2 victory against the Reds on Tuesday. He will return to St. Louis on Wednesday to be re-evaluated by team doctors.

Pujols hit a grounder to first, took a step and pulled up before falling to the ground just outside the batter's box. Pujols put very little weight on the leg as he was helped off the field by teammates.

"Based on what they come up with, we'll determine what we need to do and if it requires a roster move," Cardinals general manager John Mozeliak said. "We'll determine how we'll deal with the injury as we see fit. I'm not a doctor, so I don't want to speculate what the outcome is until they see it."

Pujols left a game against the Nationals last Tuesday in the fourth inning after experiencing tightness in his left calf. He didn't start either of the next two games but was back in the lineup against the Astros over the weekend.

"I think it's worse than the other day when he pulled it," Cardinals manager Tony La Russa said.

If Pujols goes to the disabled list, the corresponding roster move would likely be an earlier-than-expected callup of Chris Duncan, who was optioned to Triple-A Memphis on May 30 to iron out his struggles at the plate. Through six games at Memphis, Duncan is hitting .190 with no home runs.

"That would be the likely move at this point, yes," Mozeliak said. "I still want to talk with the Triple-A manager and so forth, but that's probably the move."

Pujols hit a two-run home run in the third inning Tuesday off Cincinnati's Homer Bailey, snapping a 1-for-17 slump.