The latest from Rick Hummel offers the St. Louis Cardinals' position on Albert Pujols's recent hamstring injury in nice soundbite form: John Mozeliak says the hamstring news leaves Pujols a "day-to-day" or "game-day decision", and adds that it "does not sound like anything alarming", which was probably not his exact thought process when Pujols came limping off the field against the Cincinnati Reds.
Of course, that's just how it is with Albert Pujols; he's been wincing, limping, and coming up lame almost continuously since 2003, and it's rarely serious enough to even occasion his removal from the game he's begun limping in. Pujols might not be ready for the start of the Houston Astros' series, but even given the Cardinals' notorious struggles with estimating injuries—Brad Penny and Troy Glaus come to mind—it would be a surprise to see Pujols miss more than three games with this latest hamstring issue.
Recent outfield transplant Lance Berkman and rookie first baseman Mark Hamilton are the primary candidates to keep Pujols's spot warm in the event of an extended absence.