David Robertson’s Missing Curveball

The inevitable first report: Swisher wants Werth money
Sabathia feels fine after latest bullpen session
(Greg Fiume/Getty Images)

While the middle relief has been a bit of an ongoing problem, the Yankees and their fans have to feel pretty confident when they head into the eighth inning with a lead. Rafael Soriano has been absolute money as the full-in closer, and David Robertson continues to be one of the game’s best setup relievers. He hasn’t been as outright dominant as he was a year ago, but that was to be expected to a certain extent. It’s very tough to repeat a season like that.

Robertson, 27, has pitched to a 2.45 ERA (2.55 FIP) with his usual sky-high strikeout rate (12.50 K/9 and 33.7 K%) in 40.1 innings this season while dealing with an oblique injury. His walk rate (3.79 BB/9 and 10.2 BB%) is a career-low, his ground ball rate (50.5%) a career-high, and his homer rate (0.67 HR/9 and 9.4% HR/FB) the second best of his career. Robertson’s been quiet excellent in the late innings this year, a worthy complement to Soriano.

All of that is why I think it’s pretty interesting that Robertson has basically stopped throwing his curveball in recent weeks. He’s thrown nothing but fastballs in each of his last three appearances, though one of those was a one-pitch appearance (the double play against the Blue Jays). Robertson threw three straight curveballs to start out an at-bat against Edwin Encarnacion on August 10th and he hasn’t thrown a breaking ball since, a span of 12 batters faced and 39 pitches.

According to PitchFX, David has thrown 33.2% four-seamers, 48.6% cutters, and 17.0% curves this year. Those are two career-lows sandwiched around a career-high. Last season it was 49.6% four-seamers, 26.5% cutters, and 20.4% curves. With some help from Texas Leaguers, here’s a quick little month-by-month breakdown of his pitch usage this year…

April 11 42 30.8% 53.5% 14.4%
May 3.1 17 52.4% 28.6% 19.0%
June 6.2 27 57.8% 22.5% 19.6%
July 11.2 51 26.1% 54.3% 18.1%
August 7.2 29 17.7% 63.7% 16.8%

We’re dealing with a reliever here, so the sample sizes are going to be inherently small. Add in the oblique injury a few months ago, and the samples get even smaller. There isn’t much of a trend here, other than a slight increase in cutter usage and a slight decrease in four-seamer usage as the season has progressed, assuming we kinda gloss over the oblique problem in May and June. The curveball usage is down in August but not insanely so, though that 16.8% stems from heavy usage earlier in the month and not so much recently.

Robertson has only struck out just seven of the last 38 batters he’s faced (18.4%), a span of 9.2 innings dating back to late last month. That’s roughly a league average rate, which means below average for Robertson. It seems more coincidental than anything at this point, even though the curveball is a premium strikeout pitch. He did whiff two Texas Rangers in one inning last week using nothing but the fastball, after all. Outside of the infield single and ground ball single fest in Detroit two weeks ago, Robertson has been fantastic of late and lack of curveball usage isn’t much of a concern. If his performance starts to suffer or we find out that he’s covering an injury, that’s when it’ll be a red flag.

The inevitable first report: Swisher wants Werth money
Sabathia feels fine after latest bullpen session
  • Big Members Only (formerly RI$P FTW)

    CC ate it.

    • Slugger27
      • Big Members Only (formerly RI$P FTW)

        You don’t get it! Fat Yankees jokes are the lifeblood of RAB!
        It’s edgy stuff!
        Sweaty Freddie, Fat Bartolo, Fat CC…the list goes on and on.
        See how edgy it is?

        • Slugger27

          ive never read anyone say “fat bartolo” on here. even a google search wasn’t helpful. my guess is you made it up, but correct me if im wrong. not to mention, “sweaty freddie” isn’t a fat joke.

          Bring back Rainbow Connection, for the love.

          • JobaWockeeZ

            I’ve read millions of fat Bartolo jokes on here. A quick google search shows them all

  • Ro

    I noticed this as well. Frankly, I think Robertson has had a rough season mentally. The whole closer debacle, which I attributed to his May injury slowed him down a bit. He had a handful or rough outings after that. He’s still very good, but the point I’m trying to make is he seems a little sheepish out there. I think he just needs to get his curveball some practice and back in play next Spring. It would be nice to have now, but I think he’s sticking with what works. I think he’s afraid to use it with the concern that he’ll blow a game right now. Shitty, sure, but I can’t blame the guy.

  • Eddard

    As long as he’s locking down the 8th it doesn’t matter what he’s throwing. Mo does just fine with one pitch. Robertson and Soriano will be fine, it’s the rest of the pen that should either be in the minors or DFA’d.

    • Andy Pettitte’s Fibula (formerly Manny’s BanWagon)

      That’s true to a point except the fact that when a pitcher stops throwing sliders and curveballs, it can mean that he’s having elbow pain which would be a major concern.

      • jjyank

        I hope that’s not the case, though it would worry me more if it was a slider.

    • Ben

      Yeah, lets demote everyone who has a bad game or two… outside of of Joba i think the pen is just fine. not as lock down as they have been earlier this season but still pretty good. When CC comes back we may see Phelps back in a short 1-2 inning middle relief role which should reinforce the pen.

      • G

        In the post-season we’ll have Hughes and Phelps in the pen, so as long as they can hold on and make it through with a subpar middle relief unit, they’ll be fine. It’s an easily addressed problem this offseason.

        • RetroRob

          …and Mo. : -)

          • King of Fruitless Hypotheticals

            I think I’m the only one that agrees with you, and based on my name, you’re in trouble.

        • http://riveraveblues Dennis v

          What postseason what are you been watching since the All-Star break?

  • Ben

    Who cares what he throws, as long as he is effective. one thing i have noticed is that he pitches to more contact and has been way more efficient lately.

  • Kosmo

    I seem to recall and I didn´t fact check this at all, that when Robertson first came up his fastball sat at 91-92 with a great curveball, now it seems his fastball velocity has spiked to 93-94 and I´ve seen it at 95 on occasion, so he is far more trusting in the FB than before. Either way he´s a tremendous reliever.

    Zack McAllister, remember him ? his fastball now sits at 95 a tremendous gain in velocity, it´s been attributed to a slight change in his delivery.

    • G

      Not to mention lately some of the cutters he’s thrown have pushed Mo level. He doesn’t command it the same way, obviously, but it’s got the same big, late break. He once said that on a great day he thinks he can throw it almost like Mo (and I believe Mo said he’s the closest he’s seen anyone get to it), so clearly he know it’s good. Maybe he’s consciously using it in the interest of efficiency. It’s worked lately.

      • Kosmo

        Good Point !

    • pat

      McAllister’s velocity charts say he’s still pretty much 91-92. Maybe he bumped up a mph to 92-93, but he’s not sitting 95.


  • RetroRob

    It could be intentional, just as Mariano dropping his four-seam fastball to throw more cutters was intentional. It increased his pitch efficiency. Robertson may be experimenting on his success rate using a higher percentage of fastballs to see if he can reduce his overall pitch count, without impacting results.

    Or it’s a SSS.

  • pat

    Hitters are not worthy of the CB if they can’t hit the FB.

    • King of Fruitless Hypotheticals