Minor League FIP and xFIP

One of the things that annoys me most is when a minor league pitcher will be judged by his ERA. Regardless of how his base peripherals do, people will be negative on a pitcher if he has a higher ERA or very positive if it’s low. With just how much variance there is in BABIP and HR/FB, it seems very silly for me to judge a pitching prospect based off ERA.

An example would be Marlins’ prospect Kyle Kaminska. He saw his stock jump a lot this past season. Repeating Greensboro, he improved his ERA from 6.54 to 4.16 even though his K/BB dropped from 5.81 to 3.11. But because his BABIP (.381 to .330) and HR/FB (12.3% to 6.4%), people are more optimistic about him. In reality, he more or less should have been seen as staying the course. It’s not that his stock improved, but rather than he was underrated after his 2008 campaign.

Now, FIP and xFIP certainly shouldn’t be taken as gospel. The assumption of the stat is that the pitcher is of major league quality in ability to get batted balls out. When dealing with prospects, this will be far from always being so. But I still feel it’s better to look at these stats rather than ERA. After the jump, we’ll look at how players did at each level of the Marlins’ system.

Quick notes: the xFIP is based off the expected HR/FB of a pitcher at Dolphin Stadium.  Since what we’re worried about is how a pitcher will perform at the major league level, I felt this would be better for our purpose rather than the expected HR/FB of the park they played in.  So do not view xFIP as a “this is how they should have been” at the level they were at.  If a player was in multiple organization, it only includes the stats he put up as a Fish.  If he played at more than one level, he is shown in the level he incurred the most innings.  Also, do not put too much stock into relief pitcher numbers until they reach AA, especially if they’re old for the league.  A-ball RP prospects are very, very fungible.  I included FB% instead of GB% because based on this article, FB% stays stagnant whereas GBs start to turn into LDs as a pitcher moves up.  Since a player is normally around a 18% LD rate, think of sub-32% FB rate as being 50%+ GB rate.  Now first up, New Orleans:

Although no longer  a prospect, Clay Hensley had a solid year last year and should be one of the first SP called upon should we face another injury crisis.  Rick VandenHurk had a very good season, but his high FB rates will likely hurt him a lot at the ML level.  And although I’ve seen a lot of Marlins fans question the front office in giving Hayden Penn a shot at a starting gig, he had a very solid year last year at NOLA.

On the RP side of things, Brett Sinkbeil had a very unlucky year but still was not good overall.  His GB rates are obscene, but his near 1:1 K:BB really needs to improve a lot if he’s going to come close to living up to his former hype.  Tim Wood and Jay Buente were both very solid, putting up good K/BB and high GB rates.  Both should see some time out of our bullpen next season.  Field, Santos, and Mobley are all more towards minor league filler, but could see ML time should we need help out of the bullpen.

Now for Jacksonville:

Aaron Thompson is no longer with us, as he was traded for Nick Johnson last year, but I thought it’d be a good idea to look at him.  He should develop into a decent back of the rotation guy, but it’s not too much of a loss.  I’m hoping to do a Sean West piece pretty soon to go more in depth, but I wouldn’t worry too much about the FB rates he showed last year.  He has shown throughout his career that he is a GB pitcher.  Jay Voss is one of our top left handed RP prospects, but his FB rates will likely hurt him down the road.  Chris Leroux saw some time with the Fish last year and will probably see some this coming season as well, and had a very nice year in Jax, while Stone is more towards minor league filler than a legit prospect..  And then we come to Garrett Parcell.  Parcell was the luckiest pitcher out of all you’ll see in this post, with an ERA-FIP of -1.70.  And yet he also had one of the best FIP, at 2.14.  Now he’s not this good, and at 24 he was a bit old for the league.  But he had a very impressive season last year.

Jupiter:

Do not put too much stock into Elih Villanueva‘s numbers.  Think of him like a Graham Taylor: Great MILB stats, but doesn’t have the stuff to hold up at the major league level.  He’ll probably spend next year in Jax where he’ll be put to the test.  Jeff Allison, while a good story, isn’t much of a prospect at all anymore.  Alejando Sanabia has been getting a lot of love for his ERA, but he also has a bad K/BB and high FB rates.  His ERA was powered by a 4% HR/FB and .266 BABIP.  He needs to improve back to the 3 K/BB ratio he put up in Greensboro in 2008 if he wants to become anything.  Jhan Marinez has been showing up a lot in top prospect lists, and he does pose a very good strike out rate.  But his FB rates are obscene, so he’ll need an extremely good K/BB to be an above average pitcher at the ML level if his FB rates continue to be that high.  And I already went over Winters a couple of months ago.  The rest are more towards minor league filler than legit prospects.  Though Kris Harvey, the former hitter and Bryan Harvey’s son, was added to the 40 man roster to protect him from the Rule 5 draft, so he could see some MLB time this season.

Brad Hand is probably my favorite SP prospect we have.  A left handed pitcher, he is able to post both very strong strike out rates and home run rates.  If he’s ever able to find command of the strike zone, he could be our next ace, though more likely he ends up as a mid rotation starter.  Daniel Jennings moved up to both Jupiter and Jacksonville last year, and along with Voss is one of the top lefty RP specs.  I covered Kaminska above, and outside of him the rest are more towards minor league filler.  Peter Andrelcazyk is the most interesting of the bunch, and hopefully he’ll be able to sustain those numbers as he rises through the system.  But at 23 years old in A ball, it’s hard to put too much stock into what he did last year.