2014 Phillies Report Card: Jake Diekman

Here’s a pretty thing:

Dellin Betances 135 90.0 13.50 70
Wade Davis 109 72.0 13.63 71
Aroldis Chapman 106 54.0 17.67 54
Brad Boxberger 104 64.2 14.58 63
Andrew Miller 103 62.1 14.93 73
Kenley Jansen 101 65.1 13.96 68
Jake Diekman 100 71.0 12.68 73
David Robertson 96 64.1 13.48 63
Craig Kimbrel 95 61.2 13.97 63
Cody Allen 91 69.2 11.84 76

That, friends, is a who’s who of the elite relief pitchers in Major League Baseball. Aroldis Chapman. Craig Kimbrel. Kenley Jansen. Wade Davis. Dellin Betances. Andrew Miller. And … Jake Diekman? The Phillies’ lefty from Nebraska, who was picked in the 30th round of the 2007 draft, finished seventh in the majors in strikeouts among qualified relief pitchers.

In a year that will be remembered for bad, boring baseball, the Phillies’ bullpen emerged as a bright spot for a franchise that has few. Diekman (@JakeDiekman) was one of the main reasons for that emergence, making more appearances than any other Phillies reliever, and finishing ninth in the National League in that category.

After two years of shuttling back and forth between Lehigh and South Philly, Diekman finally played a full season in The Show. As such, we should take with a grain of salt any comparison of 2014 to his 2012 and 2013 MLB numbers. Nevertheless, it’s encouraging that this year he had a career-best in strikeout percentage (K%), strikeout-to-walk percentage (K-BB%), skill interactive ERA (SIERA), and expected fielder independent pitching (xFIP). Still, Diekman’s 1.42 WHIP and 104 ERA- (ERA adjusted for park and league where 100 is average and lower is better) leave a bit to be desired.

So, how do we reconcile the fact that Diekman was one of the elite strikeout relievers in all of baseball but was also one of the worst relievers measured by WHIP? Platoon splits.

Diekman — reminder, he’s a lefty — faced twice as many right-handed batters as left-handed batters this year. Against lefties, he gave up a .232/.273/.304 triple slash (batting average, on-base percentage, and slugging percentage). Against righties, the numbers jump to .244/.363/.385. That’s not terrible, but it’s not good, and is still distinctly different than how lefties hit against the Dieker. Looking at the splits another way, lefties had a .257 wOBA against him, and righties had a .327 wOBA. So against Diekman, righties were Jacoby Ellsbury, and lefties were some kind of horrifying amalgam of Matt Dominguez and Zack Cozart.

It’s not Jake Diekman’s fault that Ryne Sandberg called on him to face so many right-handed batters. In time, it’s possible that he’ll figure out how to stop walking so many righties (30 BBs out of 213 righties faced, or 14%, compared to 5 BBs out of 100 lefties faced, or 5%). It would help if next year, the bullpen has a 6th/7th inning righthander that Sandberg trusts besides Justin De Fratus.

Grade: A-

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  1. tbarr

    October 06, 2014 02:32 PM

    no offense to the authors here, but out of 4 players (i dont count gwynn as worth mentioning) you’ve given 3 a’s. except maybe giles i didn’t see an a type performance on this team

    • Adam Dembowitz

      October 06, 2014 02:39 PM

      No offense taken. He struck out more batters than all but six relievers in baseball. If you want to call that an A- or a B+, fine. I didn’t consult the other report cards to do any kind of grade normalizing.

      • Chris S.

        October 06, 2014 02:50 PM

        I would stand behind Diekman’s grade. He was really quite fantastic except for a rough patch here and there. It isn’t easy to strike out 100 batters as a reliever and he was worth 1.1 fWAR as well as his FIP being 2.65 and his xFIP being 2.83. He was quite unlucky thanks to a .363 BABIP and looking at his peripherals he is a good candidate to be even better next year along with expected regression to his BABIP. There is a whole lot to like about Diekman and the fact that he comes at the fraction of the cost to guys like Mike Adams, Diekman had a great year. The cost effectiveness obviously doesn’t go into his grade it’s just a cherry on top.

      • tbarr

        October 06, 2014 06:34 PM

        i kinda like diekman,but his era was mediocre, his whip was lousy, his war was minus,at least according to baseball reference. the strikeouts are nice but not the only factor. not sure how the players are rated. for his stats on a lousy team and grading on a curve he could be an a. looking at stats for mid relief and loogys from other teams he is at best middle of the pack.

      • ASK

        October 07, 2014 06:52 AM

        @ tbarr,

        The mediocre ERA and the lousy WHIP make Diekman a bad fantasy player. However, if you are looking at how he performed in the categories over which pitchers have the most control – K’s, BB’s and HR’s – he was very good with the extremely high K rate more than offsetting the too high BB rate. On a site like this that favors sabermetrics and which has always preferred SIERA and fWAR to ERA and rWAR, an A- seems more than appropriate for a pitcher with a 2.64 ERA and 1.1 fWAR in 71 IP.

  2. Bob

    October 06, 2014 03:02 PM

    Diekman walks way too many batters as do almost all the Phillies pitchers. Looking at those pitchers who pitched 50 or more innings, Diekman’s 4.44 BB/9 was 308/330. That’s not good. It’s a recipe for disaster giving that many guys free passes.

    • Chris S.

      October 06, 2014 03:26 PM

      This is true, but a great way to mitigate walks is to strike people out which Diekman is very good at. Using your same criteria his 12.68 K/9 was 12/330 pitchers. It would be great if he could get his B/9 under 3, but he is still a good pitcher because he is so good at striking out batters.

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