Friday, May 15, 2009

Luckiest and Unluckiest Pitchers So Far

One of the most interesting of many, many interesting things on FanGraphs is the pitching leaderboards' E-F stat, which is simply the pitcher's current ERA minus his FIP (Fielding Independent Pitching, which I've mentioned a few times--an attempt to measure what his ERA "should" be, with defense, park and luck taken out of the equation). A negative number means the pitcher has been lucky -- the ERA is lower than it "should" be -- while of course a positive number means the opposite. So here are your leaders on both ends of the spectrum so far:

AL's Luckiest: Trevor Cahill, A's.
Cahill has put up some awfully strong-looking numbers for a rookie on a terrible offensive team: 2-2 with a 3.69 ERA in seven starts. His FIP, though, is an astronomical 6.18. Why? Well, he's not striking anybody out, at just 3.23 per nine innings, and yet he's walking more than one batter for every two innings, which gives him an awful 0.70 K/BB ratio. He's getting by right now on some combination of luck, defense, and forgiving ballparks (he's made four of his seven starts at home in the pitcher-friendly McAfee Coliseum, and another one at Safeco), having held batters to a very lucky .256 BABIP.
Prognosis: the kid's 21 years old and a solid prospect, with a minor league history of very solid K rates (one of the best in the minors in '08), respectable walk rates and almost no homers allowed, which makes me think the current flyball rate is a little fluky. He's probably not really a 3.69 sort of pitcher right at the moment, but I doubt he's a 6.19 one either. He should be fine.

AL's Unluckiest: Gavin Floyd, White Sox.
Funny enough, Floyd was one of the luckiest in 2008, with a FIP of 4.77, essentially identical to this year's 4.63. But his ERA in 2008 was 3.84; in '09 to date, it's 7.32. What goes around, I guess. Floyd is having more control trouble this year (4.81 walks per 9 to 2008's 3.05), but is balancing it so far by giving up fewer HR (0.92 to 1.31). The big difference, natch, is the BABIP: he got unbelievably lucky last year at .268, and is unbelievably unlucky so far this year at .380.
Prognosis: Problem is, I don't think the Sox or their fans would have been happy with even just a 4.63 ERA this year after what he turned in last year. So if you were expecting that, you'll be awfully disappointed. Also, the HR rate drop doesn't seem real; he's giving up about the same percentage of line drives and fly balls and has an almost identical GB/FB ratio to '08, so the only difference is that fewer of those fly balls have gone over the fence so far. That's likely to regress, so if Floyd can't find the strike zone more often, he could be in for a very rough year indeed. Just not 7.32 rough.

NL's Luckiest: Jair Jurrjens, Braves.
3-2 with a 2.06 ERA in 8 starts (48 innings), Jurrjens' start has led at least one dude (the bald guy from Princess Bride again) to believe he's quietly becoming one of the best pitchers around. But Rob Neyer always points out that it's really, really tough to succeed while striking out less than five per nine, and Jair is at 4.5, with a very unsustainable .244 BABIP. Accordingly, his FIP is 4.09 -- still very respectable, but more than two runs higher than his current ERA.
Prognosis: Well, his opponent BABIP in 2008 was a very typical .311, but his strikeout rate was a much more palatable 6.64, and so he still posted a 3.68 ERA with a FIP that essentially matched it. And he's only 23, so there's reason to believe he'll improve on even those solid numbers. His pitch speed and selection are very similar to what they were in 2008. If he can get that strikeout rate back up and start getting grounders again when it is put into play (his GB/FB ratio is less than half what it was last year) -- and I don't see any immediate reason to believe he can't -- he should be totally fine, even considerably better than the above-average pitcher his current 4.09 FIP suggests he is. He just hasn't suddenly become Pedro Martinez or something.

NL's Unluckiest: Ricky Nolasco, Marlins.
Strkeouts are good (7.5 per 9). Walk rate is up, but still very good (2.6 per 9). But his ERA is 7.78. FIP says it "should" be 4.34. Problem is, when a batter doesn't strike out against him, he's hitting almost .400.
Prognosis: That BABIP obviously can't last, even with the Marlins', um, unspectacular defense behind him. He is getting hit quite a bit harder than he was in '08 -- 26% of balls put in play off of him are line drives, compared to just 19% in both 2007 and 2008 -- which is why that 4.34 FIP is up about six tenths from last year's. He'll be fine. I mean, he won't win a bunch of games with the way the Fish are going right now, and he might not be the potential ace he looked like last year, but he's at least an average pitcher, and is probably considerably better than that.

4 comments:

  1. Nolasco's interesting, especially that high line drive percentage. You'd think, with his stuff, that that would be unsustainable. However, his pitch data indicates that he's throwing more sliders than ever before. While he threw almost no sliders in his first two seasons, 16% of his pitches were sliders last year, and almost a quarter of them have been so far this year. Sliders tend to flatten out and fatten up more than other breaking balls. I wonder if the higher LD% has to do with hitters getting more opportunities to hit a hanging slider, especially since he has relatively little experience throwing it (he really started throwing it in earnest just last year). It would be interesting to see what the opponent BA is on each pitch.

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  2. Thanks guys. That's a good point, TCM...lots more sliders. Another interesting thing is that his slider, changeup, and split finger are all clocking in within 0.2 MPH of each other. And the various internet sites that claim to know what he throws are in wild disagreement with each other. I wonder if a couple of those are really the same pitch, but he just doesn't really know what he's doing with it? Hmm.

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  3. Boy, I bet the Tigers would love to have a mulligan on the Renteria for Jurrjens/Hernandez deal

    jorgesaysno

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