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Eric Hosmer Gets the Call

The Royals went into the season stating that they were determined to see what Kila Ka’aihue could offer them as a regular first baseman, but it only took 96 plate appearances for them to come to the conclusion that Ka’aihue is no Eric Hosmer. Yesterday, they made the switch official, swapping the two between Triple-A and the majors, and Hosmer will take over at first base for the Royals this evening.

It’s easy to see why the Royals made this switch – Hosmer is killing Triple-A pitching, putting up a .502 wOBA to start the season, while Ka’aihue is struggling again at just a .282 mark. Hosmer is the future in Kansas City, and given how well he was hitting down in Omaha, it’s not hard to conclude that he’s the better player of the two right now as well.

That said, I do find it interesting how differently batting average is treated as a possessor of predictive power at the minor league level. Hosmer’s results are fantastic, but the basis of his batting line in Omaha is a .500 batting average on balls in play. Of his 43 hits, only eight of them have gone for extra bases, the kind of total you’d expect from a leadoff hitter, not a slugging first base prospect. I’m sure Hosmer is hitting the ball hard, but I’d also suggest that he’s also a bit fortunate in how many of his balls are finding holes – you don’t rack up 35 singles in a month without a decent amount of luck, no matter how hard you’re hitting the ball.

If a guy posted a .500 BABIP in the majors in April, I don’t think we’d be rushing to change our evaluation of his skills. But if a top prospect puts up a BABIP inflated line in the minors, it’s usually taken as a sign that the player is too good for his level and is ready for a promotion. In reality, though, these high BABIPs from the minors rarely carry over to the big leagues.

Freddie Freeman – a similar prospect to Hosmer, if not quite as well regarded – is going through this adjustment right now. After hitting .319/.378/.518 as a 20-year-old in Triple-A last year, he’s scuffled to a .214/.301/.365 line in the majors. His walk rate, strikeout rate, and ISO are all about what you’d expect based on his minor league totals, but his BABIP in the majors is just .242, way down from the .351 mark he put up in Triple-A last year.

Howie Kendrick, Chris Davis, Cameron Maybin, and even Kansas City’s own Alex Gordon have climbed the minor league ladder by posting high averages based on BABIPs near .400 throughout their minor league career, and yet none of them have been able to carry that over to the Major Leagues. Last year, top prospect Domonic Brown posted a .395 BABIP in Triple-A and got himself promoted to Philadelphia, where he was promptly exposed by Major League pitchers.

Even Buster Posey, who did not flop when he got to the big leagues, has seen his BABIP come falling down in the majors – he’s at .302 for his career after putting up a .386 mark in Triple-A last year and hovering in the .350 range in the year prior. My guess is that Hosmer is much more like Posey than he is the guys above who struggled to adjust to big league pitching, as Hosmer is showing terrific plate discipline and has more power than guys like Kendrick or Maybin. I’m not arguing that Hosmer is a bust waiting to happen, or that he’s going to flop upon arriving in Kansas City. He’s obviously one of the best prospects in baseball, and everything points to him having a good career as a high quality hitter.

I just wonder why so much credit is given to batting average at the minor league level as an indicator of when a prospect is ready. We know how flukey the number can be, and when you factor in low quality playing fields, a lot of poor defenders, and pitchers that aren’t usually throwing Major League stuff for strikes, it’s easy to see why there are so many high BABIP performances in the minors. The problem comes when people raise their expectations to unreasonable levels based on a guy hitting .400 in Triple-A for a month or two.

Hosmer is probably Major League ready. He’s probably going to be a good player for a long time. The Royals probably made the right call in promoting him now. None of this is a critique of the move, or the Royals handling of Hosmer this year. I will, however, suggest that we shouldn’t view it as a disappointment if Hosmer’s batting line in 2011 ends up looking something like Posey’s career mark to date – .288/.341/.468, which would represent a really nice rookie performance, and should be viewed as an accomplishment, not a disappointment, even with his staggering numbers in Omaha.