St. Louis Cardinals Former Prospect Friday: Zack Cox


Every Friday, we’ll be looking back at a player who was at one point on MLB Pipeline’s list of top Cardinals prospects, but for some reason or another never made it to the major leagues. Today we look at a first-rounder who looked to be on the fast track to the big leagues before his career took a total 180.

Zack Cox

Ranked as the Cardinals’ #3 prospect in 2011

Zack Cox, the Cardinals’ first selection (25th overall) out of the University of Arkansas in the 2010 draft, had a career about as bizarre as any first-round pick can have, absolutely dominating and reaching the upper minors in his first professional season before proceeding to completely fall of the face of the earth and disappear from baseball within five years.

After signing with the Cardinals in August of 2010, Cox was sent to the Arizona Fall League and began the next season in High-A ball. He looked to be on the fast track to the big leagues, and that likelihood was also heightened when he hit .335/.380/.439 in his first 42 games with the Palm Beach Cardinals. That earned him a promotion to Double-A Springfield, where he dominated in similar fashion. Over 93 games in Double-A, Cox hit .293/.355/.432 with 10 homers, leading to the understandable expectation that he’d be a major-leaguer sooner than later.

Cox went into the 2012 season ranked 66th overall on the Top 100 prospects list published by ESPN’s Keith Law. Unfortunately, Cox’s development took a turn for the worse that year.

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Cox was promoted to Triple-A to start the year, but while dealing with a multitude of injuries, he posted a much more pedestrian .254/.294/.421 slash line with nine homers in 316 plate appearances with Memphis. The defensively-limited Cox was made expendable when the organization took three third basemen—

Stephen Piscotty


Patrick Wisdom

, and

Carson Kelly

—in the first two rounds of the 2012 draft, and his fate with the Cardinals was sealed at the trade deadline, when in a surprising turn of events, he was dealt to the Miami Marlins in exchange for

Edward Mujica

, a reliever who had posted mediocre results with the Marlins but went on to be much more effective in St. Louis.

In retrospect, Cox’s worst decision—one that would soon after be banned in major-league baseball because of its downright stupidity—was demanding a major-league contract and a spot on the 40-man roster immediately after the draft. While there were some benefits to this request—it guaranteed him a much more desirable salary floor, and it somewhat forced the organization’s hand in terms of moving him up the minor-league ladder—it forced the club to exhaust all of his minor-league options during his first three professional seasons.

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In a way, that request came back to bite Cox, who was designated for assignment by the Marlins in spring training of 2013. While he still had an option remaining, Cox’s 40-man roster flexibility was going to be an issue going forward, and the Marlins obviously decided that after he posted unspectacular results over the remainder of the 2012 season at Triple-A, he wasn’t going to be a long-term answer.

Cox had mixed results over three more seasons in Miami’s system. He struggled with injuries and eventually was demoted back to Double-A in 2013, but he rebounded the next year, returning to Triple-A and posting a solid .282/.344/.436 slash line with eight homers in 344 plate appearances. A banner year by the Marlins’ major-league starter, Casey McGehee, prevented Cox from getting a chance, though, and still failed to break into the big leagues.

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His career was all downhill from there, as he was sent back to Double-A to begin 2015. While he put together a solid campaign over four months there, he was promoted back to Triple-A to finish the year and went just 11-for-55 the rest of the way. Cox was selected by the Washington Nationals in the minor-league portion of the Rule 5 Draft this past winter, but was released at the conclusion of spring training. This year, he’s been playing for the an independent club, the Wichita Wingnuts, and while we’ve seen plenty of instances of guys going to independent ball and then reviving their careers before, long gone are the days where Cox was considered a promising future big-leaguer.