Jenrry Mejia and the dominance of the extreme GB pitcher

Jenrry MejiaIn his short major league career, Jenrry Mejia has generated a 61.3% ground ball rate. With league average at 44.6%, Mejia’s ability to facilitate contact on the ground speaks to the movement he inflicts on a baseball.

Very few pitchers have pitched seasons with a GB% at above Mejia’s 61.3% in the past 12 years, as far back as FanGraphs reports.

Player Year GB% Innings WAR Notes
Derek Lowe 2006 67% 218 4.1
Lowe 2002 66.8% 219.2 5.4 21-8, 2.58 ERA, 3rd place Cy Young voting
Brandon Webb 2006 66.3% 235 6.3 Cy Young Award Winner
Lowe 2003 65.9% 203.1 3.0
Lowe 2007 65.0% 199.1 2.7
Webb 2005 65% 229 4.6
Webb 2004 64.3% 208 2.5
Roberto Hernandez 2007 64.3% 215 3.7
Webb 2008 64.2% 226.2 5.5 22 W, 2nd place Cy Young
Tim Hudson 2010 64.1% 228.2 2.3
Webb 2003 63.9% 180.2 4.4
Lowe 2005 63.1% 222 2.3
Chien-Ming Wang 2006 62.8% 218 4.1 2nd place Cy Young
Jake Westbrook 2004 62.6% 215.2 3.4
Kevin Brown 2003 62.5% 211 5.4 2.39 ERA
Lowe 2004 62.3% 182.2 3.0
Hudson 2007 62.0% 224.1 4.6
Webb 2007 61.8% 236.1 6.2 2nd place Cy Young
Westbrook 2005 61.8% 210.2 3.3


-          Mejia’s sample size is not large enough to say with confidence that he will repeat his GB% over the course of an entire season.

-          Mejia’s GB% in the minors mirrors but does not exceed, as an average, what he has pitched to in the big leagues. Some seasons, though, are far higher. With the addition of a new and seemingly effective slider, the expectation for extreme GB% should continue.

-          Notice the innings pitched in the chart above. In 14 of the 19 seasons in which a pitcher’s GB% was above 61.3% for a qualified season, that pitcher threw at least 210 innings.

-          No pitcher has pitched to a rate of 62% in any of the past three years.

-          Notice the WAR in the above chart. The average of all of these seasons is 4.04 fWAR.

-          Many pitchers have success by obtaining outs in the air. Justin Verlander and Johan Santana are two of many who regularly pitched with low ground ball rates and have won many Cy Youngs doing so. However, the upper echelon of ground ball pitchers have had equal, if not better, success. Reducing the GB% to 58%, names like Roy Halladay, Felix Hernandez, and Greg Maddux start to appear.

In conclusion, the campaign for Mejia as the 5th starter on the 2014 Mets should already be have strong support following his handful of brilliant starts in 2013. Short of an injury or a poor spring performance, there would be no reason he does not get every opportunity to start games for the Mets this year. Despite his likelihood of starting in the big leagues this year, it is worth noting just how dominant extreme ground ball pitchers have been. Mejia, with his impressive movement, assortment of breaking pitches and history of high ground ball rates could become one of these pitchers.

A 4.0 fWAR is an All-Star performance. Only 21 pitchers achieved that mark in 2013. Of the 21 to reach this mark, 14 were pitchers with above average ground ball rates. There have been a number of rumors about replacing Ruben Tejada with a bat-first, fringe-defense young shortstop from another team. If there is no other reason for keeping Ruben Tejada, consider how many ground balls are going to be on the infield with the likes of Mejia, Niese, Syndergaard, Wheeler, and Gee —all ground ball pitchers— facing opposing batters. Infield defense will be paramount for the 2014 Mets. Murphy already defends at a below average (yet acceptable) rate. A shortstop who reduces the quality of the infield defense goes a long way towards letting more runs cross the plate. That cannot happen.

Mejia has a talent that could be team changing. His ability to generate ground ball outs, maintain a high strikeout rate, maintain a low walk rate, and limit his pitches per inning could not just make him a solid starter, but one of the better arms in the National League. Keith Law recently opined that Mejia still has the ceiling of a number-two starter in baseball. In light of this data and having seen his potential last year, Law might be on to something.


 Have a baseball question? Ask me on Twitter (Stephen Guilbert @guilbs88) or post in the comments below.

17 comments for “Jenrry Mejia and the dominance of the extreme GB pitcher

  1. amazin
    February 23, 2014 at 10:19 am

    Tejada is at best an average short stop defensively. I rate him as below average. If you must have a short stoop that can’t hit can’t you at least have one that is good defensively?

    • Stephen Guilbert
      February 23, 2014 at 11:22 am

      And I rate Tejada has above average but certainly not elite. I don’t particularly care if you trade for Gregorius, give Tovar the job, or if Flores was touched by the hand of a deity this winter and can truly defend at a gold glove level, you have to prioritize infield defense with this pitching staff. Tejada rates above average in each of the past three seasons defensively on FanGraph’s defensive metrics but drs has him at or slightly below average, as you say. My point is, you have to go with that over Franklin or Flores who will let many more balls through than Tejada. I don’t think that’s debatable. I’d rather not lose a draft pick and spend 10 million or more on Drew, so I’m left with advocating for Tejada. If you see a better solution at shortstop, let me know. Perhaps I’ll pen an article about it.

      Also, to be fair, Ruben is a light hitter but he does get on base pretty well, so his offensive contributions are limited but not nil.

      Thanks for the comment.

  2. February 23, 2014 at 11:22 am

    I’m a big Mejia fan and I’ll be disappointed if he doesn’t make 20 or more starts for the Mets in 2014.

    In the beginning of your article, you said that the average GB% was 44.6 and later on you called Wheeler and Gee ground ball pitchers. But they were both below average in the category last year, at 43.2 and 42.6, respectively. Also, Bartolo Colon had a 41.5% mark last year.

    Syndergaard has been a ground ball pitcher most of the time in the minors. But when he was promoted to Double-A last year, he had a 39.8 GB%. It could be nothing more than a sample size issue but it bears watching this year.

  3. Stephen Guilbert
    February 23, 2014 at 11:29 am

    Dillon Gee for his career- 46.0%
    Zack Wheeler minor league GO/AO by year- 2.68, 1.29, 1.20, 1.06. Not nearly as extreme as Mejia but I would describe him as a ground ball pitcher and I think we’ll see more of that this year than the small sample size of 2013.
    Syndergaard- 1.75, 1.30, 2.16, 1.11. Also, if you haven’t read his ideology about getting a hitter to ground out weakly, I recommend it. It’s a unique and highly conscious approach for a 21-year-old pitcher.

    Colon- Fly ball pitcher in every sense of the word. I do not believe I suggest otherwise. Farnsworth for his career has been, although recent seasons he has transitioned into a GB pitcher. Edgin, Dice-K, and Valverde also prevalent fly ball pitchers.

    • February 23, 2014 at 11:40 am

      No, you didn’t say anything about Colon. But when discussing the defensive needs of the 2014 team, it should be noted that Colon is not a GB pitcher. Wheeler’s lifetime GB% in the minors is 43.8 so he’s not going to be remotely like Mejia, who had a 52.5 GB% in the minors. We’ll have to see if Gee’s 2013 was a one-year blip or the beginning of a trend.

      • Stephen Guilbert
        February 23, 2014 at 12:11 pm

        I’m looking at 1.11 GO/AO as league average and Wheeler and Syndergaard above that. Another thing to consider is how many outs in the air more were made from actually having good outfield defense last year. Needless to say if only one of our starters and a couple relievers are fly ball pitchers and the rest are either gb machines or flirt with league average at worst, you can’t get by with bad infield defense and expect to win. Bad defense up the middle like Flores-Murphy or Franklin-Murphy shouldn’t happen on any team looking to win..muchless one that has a gb tendency staff

        • February 23, 2014 at 12:30 pm

          I don’t know why you start out using GB% and then change stats in midstream.

          Regardless, we haven’t even discussed the possibility that the veteran fetish of Terry Collins wins out and that Daisuke Matsuzaka breaks camp as the fifth starter. He has a 36.0 lifetime GB% and last year with the Mets it was 28.3%

          • Stephen Guilbert
            February 23, 2014 at 1:25 pm

            Because I cannot find data for minor league GB% but milb does list GO/AO rates. Instead of comparing something to nothing, I opted to compare something to something–albeit a tad different.

            If Dice-K does in fact make the rotation, yes, this thesis changes.

            Regardless, this article was meant to be about Mejia and the dominance of the fastball…not a trial of Ruben Tejada.

            • Stephen Guilbert
              February 23, 2014 at 1:25 pm

              Dominance of the ground ball***

            • February 23, 2014 at 1:28 pm

              I’ve been quoting minor league GB% throughout and you can get it at Minor League Central.

  4. Jerry Grote
    February 23, 2014 at 12:12 pm

    I’m a proponent of defense, but over the course of a season runs prevented and runs scored
    are roughly equal.

    A SS with lower range is going to be providing the other teams, in all likelihood, singles. Obviously there are few doubles hit to SS. A SS with good power, OTOH, will be trading up XBH.

    In the mid 80s, according to Bill James, Ozzie Smith was able to get to about 30 more assists than the average SS. His peak levels were around 45ish.

    Could Franklin really be so bad, that he makes Tejada seem like Ozzie Smith in comparison? Can Ruben contribute 30ish more outs than Franklin?

    Seems like a stretch to me. Given the Ruben can’t even seem to play 125 games … anyways, for me it gets down to total contribution. This team cannot afford a 625 OPS hole at SS, *especially* if you are playing Juan Lagares in CF, *even if Tejada is fielding as well as you say he is*.

    TO this same extent, I think MetSense posted up a link on the declining importance of defense on Hardballtimes. Pretty good read.

    • Stephen Guilbert
      February 23, 2014 at 1:47 pm

      Jerry, you bring up excellent points and, honestly, I could probably write a counter article to this just as easily using the points you bring up. In fact, if might be a good exercise for me to do to challenge my convictions. Here is what I would offer as a counter-argument to that non-existent article:

      - “Could Franklin really be so bad…” honestly yes, he could. In lieu of knowing if he’s going to hit like Tulo or if he’s going to hit like Cozart, I don’t know if he’s going to generate more runs than he’d allow via defense.

      The formula Ruben DRS+RC > or < than Franklin DRS+RC is not the only thing to consider. If you have to think about that, you don't trade for Franklin. He's not going to come free. If he were, I'd grab him in a heartbeat. If he's not ready for major league pitching, I send him to Vegas for the year, try him at second and short, and if he truly is a 2B, you deal with that situation in a year.

      I do understand not wanting Lagares and Tejada in the same lineup. If both hit like they did in 2013, that's a disaster. I do know that. Even so, the Mets as a team last year with 3/4 of a season from Lagares and more than half a year from Quintanilla…even worse hitter than Tejada….still finished in the top half of baseball in runs scored (12th as a matter of fact. Don't ask me how that happened…I actually have no clue). And yes we've lost Byrd but we have gained a full season from TdA, Granderson, and Chris Young. So I'm not terribly worried about short and center if we can continue to manufacture runs other ways.

      Look, if Franklin were Javier Baez, I wouldn't care nearly as much about his defense. If you're thinking I'd pass on a true offensive threat because of poor defense, you're wrong. I do not trust Franklin's bat as much as most. I see an extremely long swing and contact issues that could be exploited against good pitching. Considering I have to pay handsomely in prospects for this player, and that he is a question mark offensively and a downgrade defensively, I'd pass. Again, this isn't "Ruben Tejada against the rest of the shortstops in baseball", this is "Of the options we have and considering we have a staff that generates a lot of ground balls, Ruben is a better option than Franklin". I stand behind that although I do see your points.

      Again, this article was not meant to be about indicting or endorsing Ruben Tejada but rather a look into how good Mejia can be if he continues to generate ground balls at the rate he has through 92 major league innings. I should have saved the opinion on Tejada for a different article.

      Final note: Looking at Drew's numbers, you do see a strong defender there across defensive metrics. He passes the eye test and has always been considered a strong defender. If you want to give him 10 million and surrender a draft pick *but* improve the offense (albeit probably not much) and solidify up-the-middle defense, that's an argument I think worth making. Trading a good prospect for a shortstop that's probably not suited for the position when you already have Murphy is tough..regardless of if your pitchers are GB-heavy or not. Again, if we're talking about two players with the offensive profiles of Tulo and Cano at second and short, I wouldn't care about their defense. Murphy and Franklin, though? I don't see those two manufacturing enough runs to justify the defensive deficiencies they bring.

      That's my .02. Thanks for commenting. You always provide a nice counter even though we typically agree on defense, lagares, ruben, etc.

      • Stephen Guilbert
        February 23, 2014 at 1:52 pm

        Ah jeez poor research on my part. I had the 2011 season opened up. That’s the season we finished 12th, last year we were below league average by about 9%. I still think the Granderson/TdA/Young upgrades should give us a boost but it’s not like we’re going to be a run-producing machine either.

  5. Stephen Guilbert
    February 23, 2014 at 1:35 pm

    Ah, fantastic. Here we go. Wheeler:

    2011: 5.7% above league average GB%
    2011: 0.7% above league average
    2012: 1.4% above
    2012: 2.3% above
    2013: 3.7% below

    Again, I would say that’s a ground ball pitcher but if you want to look at the trajectory and say he’ll be right around league average, I can’t blame you. He has generated a higher gb% than his peers as a professional, though.

    • February 23, 2014 at 1:53 pm

      That’s an interesting reading of those numbers. The very first line, the one where he’s 5.7% above-average, came in 110 PA. The next biggest variation from the norm came last year. You split the other seasons but you only have one line for 2013. I don’t know if that means his Triple-A numbers only or his full-season output. If it’s the former, then that’s 291 PA and if it’s the latter, it’s 669 PA.

      Either way, it’s a larger sample than his 2011 partial and it’s more recent, so I would give that more weight.

      • Stephen Guilbert
        February 23, 2014 at 1:55 pm

        Those were just his minor league numbers. He only played in one league in the minors in 2013, Brian. We’ve already mentioned where his GB% was relative to league average as a major leaguer.

        • Stephen Guilbert
          February 23, 2014 at 1:59 pm

          669 batters faced below league average, 1103 batters faced above league average. Again, I maintain that he has ground ball tendencies but if we’re going to use the ideology that upper minors/recent minor league data holds more weight, I’d ask that we do the same for Juan Lagares when considering his offensive potential. Just a thought.

Leave a Reply

Your email address will not be published. Required fields are marked *