MLB Dirt

Chris Lee/St. Louis Post-Dispatch

Peter Gammons is reporting that the St. Louis Cardinals are shipping third base prospect Zack Cox to the Miami Marlins in exchange for right-handed relief pitcher Edward Mujica. The Cardinals are adding Mujica in an effort to bolster their bullpen which boasts the second worst fWAR total at -0.2 and the third worst FIP and HR/9 rates in the Majors.

The Cardinals needed to add a bullpen arm but probably could have received a better one for trading third base prospect Zack Cox, the 25th overall pick in the 2010 MLB draft, despite his fall from grace as a prospect in his first season in Triple-A.

Cox came into the 2012 season ranked 90th on my overall prospect list and 6th in my St. Louis Cardinals top prospect list. After hitting .306/.363/.434 across High-A and Double-A last season Cox has fallen to a disgraceful .254/.294/.421 line in 2012 which is a 79 wRC+ in the Pacific Coast League.

Cox, still only 23, saw his strikeout rate increase 2.2% and his walk rate decrease nearly in half from 7.0% to a dismal 3.8% this season. The only positive has been that his ISO has increased. His defense has yet to improve and there are questions as to whether or not he is even average at the position. He still has a chance to fulfill his promise of becoming an above-average regular with an outside shot at an All-Star appearance or two but he will never reach it if he does not clean up his approach and defense.

Mujica is not a bullpen savior but he is an upgrade over what St. Louis has mostly been throwing out there. Mujica has a good fastball in the 90-93 mph range and he pairs it with a splitter that has been excellent in the past and he will also mix in a fringe-average slider. Mujica started using a two-seam fastball for the first time and has used it more than his four-seam fastball which has lead to a career best 50.4% ground ball rate, 10% higher than his career mark coming into the season.

Mujica has seen his K/9 decrease for the third straight season and his BB/9, which was his calling card, increase for a third straight season but it is still at a respectable 2.08. Mujica remains homer-prone with a 1.38 HR/9 that is only slightly above his 1.29 career mark and his current 4.51 FIP is the worst mark of his career in any season with more than 13 innings pitched. Mujica still has one year of arbitration left after making $1.65M this year.

Cox may be a fading prospect who never pans out but he still has the potential to be a good player and to trade him for a replacement level relief arm that will cost you over $2M if you tender him a contract next year is a waste of farm system resources even if a replacement level arm is an upgrade over your current 12th man.

-Jonathan C. Mitchell can be found writing about the Tampa Bay Rays at DRaysBay and the Florida Marlins at ESPN’s SweetSpot site Marlins Daily. You can follow him on twitter at @FigureFilbert. Be sure to follow MLBdirt at @MLBdirt

Filed under: Digging Deep - Analysis Tagged: | Edward Mujica, Miami Marlins, St. Louis Cardinals, Trades, Zack Cox