ST. LOUIS -- The Busch Stadium Rally Squirrel's days of running around the ballpark could be numbered.

Or not.

Joe Abernathy, vice president of stadium operations, said his staff has caught four squirrels, and safely released them into the wild, since Game 4 of the National League Division Series after a squirrel -- or squirrels -- made appearances on the field during Games 3 and 4.

But Abernathy said he couldn't be certain they've trapped the Rally Squirrel, who has become famous among baseball fans and even has a Twitter account (@BuschSquirrel) that has more than 23,000 followers.

"We were successful in trapping four squirrels but have seen other squirrel sightings, and do have traps out, so the Rally Squirrel could still be out there," Abernathy said. "So maybe he could surprise and make another appearance."

The Rally Squirrel made his arrival during Game 3 of the NLDS, when he ran around the outfield and down the third-base line to briefly interrupt the game with Ryan Theriot at the plate in the sixth inning.

But it was in Game 4 that the Rally Squirrel took center stage, as it darted across home plate just moments after Phillies right-hander Roy Oswalt threw a pitch to Skip Schumaker. The squirrel then ran into the stands as Oswalt protested that the pitch, which was called a ball, shouldn't have counted because he was distracted.

The return of the Rally Squirrel captured the imagination of television viewers, Cardinals fans, and even manager Tony La Russa, who joked on Tuesday that the squirrel was simply trying to find outfielder Allen Craig, whose tortoise has also become an internet sensation with the popular Twitter account @TortyCraig.

"As far as the squirrel and the tortoise is concerned, they had this relationship, so I think it first came out there because Craig wasn't playing, and his boyfriend told him or girlfriend or whatever it was, and this squirrel was looking for Craig, ran all over, finally found him," La Russa said.

So while the Brewers have Beast Mode, the Cardinals have their Rally Squirrel and they're having fun with it, causing some of the players to joke about how the squirrel is a good luck charm.

"He or she, I don't know what it is, but that squirrel's got something," third baseman David Freese said with a smile.

The Cards' marketing team is also taking full of advantage of the Rally Squirrel's appeal among fans, as they're handing out rally towels featuring the Rally Squirrel to the first 40,000 fans at Game 3 of the NLCS on Wednesday.

Additionally, starting Wednesday, the Cardinals will begin selling stuffed Rally Squirrels for $5 at the official team store at Busch Stadium, as well as "Got Squirrel" T-shirts.

"It's one of those neat things that comes around during postseason baseball, whether it's a song or gesture or even a squirrel," Abernathy said. "Every year something comes up, and so this year, this is our twist."

La Russa, for his part, is also enjoying the celebrity status of the Rally Squirrel and noted that the fun surrounding the famous critter has helped keep his players loose during the postseason.

"I think it's good," La Russa said. "The fans are having fun. And I really believe that this is not old school, and I know I am in many ways, but I think there's so much attention and pressure on the players that sometimes they don't show their happiness. I've really gotten over getting upset over it. Sometimes I think it's a release. So I think it's fun."