ST. LOUIS -- The Cardinals have an ace in the hole, and it appears they are ready to play their trump card.

In his long return after having Tommy John elbow reconstruction surgery on his right elbow, Chris Carpenter will begin his rehabilitation in the Minor Leagues on Sunday. Within 30 days, the Cardinals expect him to rejoin the club.

For a team that has chugged along with a makeshift starting rotation for most of the season, his return -- along with Adam Wainwright's -- will be a much needed lift for the team in in the second half of the season.

"I think it would be huge," general manager John Mozeliak said, "assuming [Carpenter and Wainwright] are able to contribute to the level we're expecting. I do think it will be a great lift for us."

For the past two weeks, Carpenter has participated in simulated games in Jupiter, Fla., with his most recent on Monday.

Carpenter will make his first appearance Sunday with Double-A Springfield. With strong reports on Carpenter out of Florida, the Cardinals are not hesitating to get him some tougher action immediately.

"It's a good spot to start, and he wants to face a higher level," Mozeliak said.

Mozeliak added Carpenter's arm strength is fine, and his ability to throw a high pitch count is adequate. The club is mostly focused on their ace fine-tuning his stuff to be game-ready.

The Cardinals have up to 30 days to put Carpenter through a rehabilitation program, and Mozeliak said he is unsure if they will use the full 30 days. But there is no urgency to rush Carpenter back to the Majors before he is ready.

"This whole year has been based on trying to get ourselves healthy," Mozeliak said. "We haven't accomplished it. However, we have been able to hang in this race and still win games. At this juncture, there's no reason to change our plan."