With the Cards clinging to a one-run lead in the sixth inning of their 5-3 win over the Phillies at Busch Stadium, starter Edwin Jackson allowed a leadoff walk to Chase Utley.
With Hunter Pence up, Phils manager Charlie Manuel called for a steal. Pence hit the ball to shortstop Rafael Furcal -- who, with Utley running, only had one play, and that was to first base.
But the ball never got to first base.
Pujols, seeing that Utley didn't stop at second base, came off the first-base bag and made a throw to third baseman David Freese to nab Utley.
How big was that play? If Utley would have been safe at third base, then he probably would have scored on Ryan Howard's fly ball to center field.
"You need to be alert, obviously; this is the playoffs," Pujols said. "With nobody out, I decided to try and get the guy at third. It killed the rally right there."
To a man, teammates inside the Cardinals' clubhouse -- those who are typically used to commenting on something Pujols did with the bat -- were amazed at the play he made with his arm.
"For Albert to even think to do that ... I don't know how many guys are able to make that play," said Cards left fielder Matt Holliday.
Utley said that he was just trying to be aggressive on the play.
"I was stealing, the ball was hit in the hole and I thought I had a chance to get to third, and Albert made a pretty good play to get me out," he said.
Manuel didn't have a problem at all with Utley taking a chance on the bases.
"I think he was very aggressive," Manuel said. "I think that when the ball was hit, he thought he was being aggressive. He was trying to make something happen.
"I think Pujols was the key in that play, because he read it. If you noticed, he came right off the bag and got in a good position to throw the ball."
Not bad for a player who has largely built his credentials as the best of this generation with his prodigious bat.
Just don't pigeonhole Pujols as a one-dimensional player, said Cardinals manager Tony La Russa.
The Phillies certainly won't, as the series now shifts to Philadelphia for Game 5 on Friday.
"We talk about it all the time ... tell people he's a great player. And the way you're best doing it is just to explain actual things that he does that are great," La Russa said. "He does it with baserunning. His defense is great. He's always got an awareness of what the score is, and that's part of his greatness.
"He plays the whole game in a great way."