Tuesday, May 29, 2012

Minor League Breakdown: The Pitching Prospects

Overall state of the farm

The positive trend of the last weeks couldn't be continued by the minor league affiliates in the last week. Combined, the full-season ball affiliates had a record of only 9 wins opposing 14 losses. Especially the Stone Crabs with 5 consecutive losses haven't helped their playoff chances last week. Sad stat of the day: Since this week, the Durham Bulls are LAST in pitching (according to ERA) AND in offensive production (according to OPS) in the International League!

OPS-CH and ERA-CH stands for the OPS and ERA change since the last minor league breakdown.

Nevertheless, I want to focus on the positive pitching trend since the start of the season, by pointing out two facts:
  1. As can be seen in the graph below, the ERA decreased since the start of the season. Especially Durham and Montgomery have improved their pitching outcome in the last month. 
  2. The FIP over all Rays minor league pitchers is 3.53 on the season. This means, that the FIP is 0.63 lower than the ERA, which suggests that the pitchers as a whole are better than their ERA suggests. The reasons can be simple bad luck or below average performances by the defense. The FIP over the last week was even lower than 3.53, with 3.34.
ERA change since the start of the season

Prospects stats overview
(click on the image for a better view)

Prospects on the rise
  1. Brandon Gomes ... While having only 16 IP (in the minors), he looks very dominant. Nearly 15 K/9 (which is a ridiculous 41.9 K%) and a 4.33 K/BB-ratio over the season (16.2 K/9, 6 K/BB ratio and 0.50 FIP over his last 10 IP) are excellent. Also considering his MLB success last year, he definitely should be the 1st reliever being called up in case of an injury.
  2. Chris Rearick ... The 2nd reliever on the list of rising prospects continuous to shine like last year. 12.91 K/9 and a 1.50 FIP are not bad at all. In comparison to Brandon Gomes, his BABIP does even suggest that he was a tad unlucky so far (the FIP is also lower than the ERA). 
  3. Grayson Garvin ... With C.J. Riefenhauser having been on every "prospects on the rise-list" so far, Grayson Garvin is the only starter on this one. Garvin quietly puts up one solid start after another. A FIP of 2.22 over his last 23.2 IP with 8.4 K/9 and 2.7 BB/9 are excellent.
  4. Romulo Sanchez ... The reliever nr. 3 on this list could be a dark horse for the big league club later this year. After some struggles at the beginning of the season, he hasn't been anything than dominant since - and that with pinpoint control!. 9.9 K/9, 0.7 BB/9 over the last 13.2 IP are mind-blowing.
  5. Wilking Rodriguez and Alex Torres ... It probably is too early to put them here, but it's nice to see some progress as of late.

Prospects to be falling
  1. Johnny Nunez ... While Brandon Gomes and Romulo Sanchez are pushing for the show, I'd be surprised to see Johnny Nunez being called up this season. No control (9.6 BB/9 in last 10.1 IP and 6.56 BB/9 over the season) and a FIP of 5.64 (7.16 over last 10.1 IP) are neither helping his cause nor the Durham Bulls.  
  2. Braulio Lara ... Entering full-season ball with lots of fanfare and hype, his results give us a hint that he hasn't progressed very much over the last 2 years. A K/BB ratio of only 1.37 (5.9 K/9, 4.3 BB/9) over his last 16.2 IP are not helping either.
All of the stats provided above are excluding the stats from the previous day. I preferrably use FanGraphs as source for the stats. Click on each stat for its explanation:


  1. This gives me the chance to ask, what constant are you using to calculate FIP? American League or some other number? Could that account for the delta you're seeing between ERA and FIP? I like FIP, but that "constant" has always bothered me. I know it's used to let us compare FIP to ERA, but maybe it would be better to just have a "pure" FIP when you're going across leagues like this?

    1. Hi Chris,

      Thanks for the question. As Doug already mentioned below, it should be around 3.2 as I take FIP from Fangraphs.

      If they don't automatically calculate the constant for each league (which they should ... and which I expect them to do, as their statistics normally are excellent) by subtracting the league average FIP (without the constant) from the league average ERA I'd be surprised.

      With the assumption that they do it, the comparison is working. Otherwise, you are right, it's not. The constant could simply be too high (or low in this case with a low FIP) and therefore misleading.

      Next Breakdown (of pitchers) I'll calculate it and compare it to the FIP of Fangraphs to make sure. Thanks for the idea!

  2. Isn't it just 3.20? Back when I kept spreadsheets for all the pitchers that's what I used, but it's been a few years.

  3. I think, but am not sure, that the 3.2 is the American League average from several years ago. And that's what I use with my home-brewed FIP calculations. But for my purposes (I'm obsessed with trends) it doesn't really matter much. I could use "pure" FIP and may do just that the next time I do one of my charts. It's a bit like when the used to use reaching on an error in the wOBA calculation and then dropped it, but added steals and caught stealing. Was never sure why and never had enough energy to chase it down.
    Nice work, BurGi.

  4. FIP is the dumbest stat that was ever invented. You have a team playing defense as well which is part of the game!