The Cardinals have acquired three-time All-Star Matt Holliday from the A's, SI.com has confirmed. The deal was approved by the commissioner's office Friday afternoon.

The A's received three prospects in the trade: coveted third baseman Brett Wallace, outfielder Shane Peterson and right-handed pitcher Clayton Mortensen. The A's also sent $1.5 million to St. Louis, covering most of Wallace's $1.8 million signing bonus from 2008.

Holliday, a career .315 hitter, has seen his offensive numbers drop across the board since leaving the hitter-friendly Coors Field in a trade between the Rockies and A's in November. He is currently hitting .286 with 11 home runs, 54 RBIs and 12 steals, though July has been his best month of the season (as evidenced by his .338 batting average and .574 slugging percentage).

"I know his numbers are down, but I still think he's a great player," one AL executive said.

Holliday has also been very fond of the new Busch Stadium since the park opened in 2006. Holliday's career numbers at the Cardinals' home park: .385 AVG, .872 SLG, 1.350 OPS (highest at any park, min. 10 games). He should provide solid lineup protection for the game's top hitter, Albert Pujols.

The 29-year-old slugger is eligible for free agency after this season.

The Cardinals took Wallace with their first selection of the 2008 draft, and did the same with Mortensen in '07. Peterson was taken in the second round of the 2008 draft. The crown jewel of the deal for the A's is Wallace, who was the top hitting prospect in the St. Louis organization and boasts a solid power stroke. But some executives question whether Wallace can remain at third base, making the American League a better fit with the designated hitter. One NL executive said he sees Wallace as a first baseman. "He's not a third baseman, but he can really hit,'' the exec said.

KEITH: Holliday provides Pujols protection

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