The 4 best trade deadline moves in Cardinals' franchise history

The Cardinals land Matt Holliday in another lopsided trade with the Oakland Athletics in 2009.

Oakland should be wary when trading their stars to the Cardinals at this point. For the second time in about two decades, St. Louis was able to snag a perennial All-Star while sending players back to Oakland who wouldn't pan out. This time, it was for an outfielder: Matt Holliday. Holliday would become a cornerstone in St. Louis for many years after this deal.

In what was one of John Mozeliak's biggest moves early in his tenure as general manager, St. Louis sent Clayton Mortensen, Shane Peterson, and Brett Wallace to the Athletics for corner outfielder Matt Holliday. At the time, this deal was a bit risky. Brett Wallace was one of the best prospects in baseball, and Clayton Mortensen was rising in the Cardinals' farm system. Peterson was a recent second-round draft pick.

Sending three young players with full team control to Oakland for an outfielder who was a free-agent-to-be was quite bold. If Holliday were to sign elsewhere, the trade would be maligned by fans. If any one of the prospects panned out to be as good or better than Holliday in St. Louis, the trade pendulum would swing dramatically in the other direction.

Instead, this deadline deal from 2009 couldn't have gone better for the Cardinals. Wallace was a below-average hitter with poor defense, Mortensen struggled to maintain a major league roster spot, and Petersen wasn't even a replacement-level hitter for his career.

Meanwhile, Matt Holliday would garner MVP votes in four of his seven seasons in St. Louis and go to four All-Star games. Holliday was also awarded a Silver Slugger trophy in 2010 with St. Louis. Some of Matt Holliday's best years came in St. Louis, and the lack of production from the players who went to Oakland made this deal at the deadline one of the best in St. Louis history.