Diagnosing Aroldis Chapman’s Wildness

Yesterday, in a game against the Houston Astros, Aroldis Chapman entered the game in the top of the 8th inning and faced four batters; he walked three of them and hit the other. That leaves Chapman with a league-leading 11.37 walks per nine innings, 16 walks and two hit batsmen in 12.2 innings. In his 15 innings last year (including the playoffs) he walked just five batters and hit one.

Obviously these are tiny samples of innings, but going from three walks per nine to over 11 is alarming. His BIS-reported Zone% is down from 43% last year to 38% this year. Here are the locations of his fastballs to right-handed batters in 2010 and 2011 to see where he is missing:


In 2010 the diagonal swath of his fastballs was centered roughly on the strike zone. Since he was throwing in the high-90s and regularly into the triple digits this was fine. He has whiffs on some pitches right in the heart of the zone. But in 2011 that swath of fastballs is centered higher and further inside. He get some swings on his out-of-zone pitches — particularly those inside — but for the most part they end up as balls.

There is also a conspicuous difference in Chapman’s “release point.” The Pitch F/x system estimates the trajectory of each pitch and then reports where it was 50 feet from the plate. This is too close to be the real release point. We don’t know exactly where the pitch was released, but it is best to pull the pitch back some. For tall pitchers with a long stride, like Chapman, 53 feet is a good estimate. See Mike Fast’s great article on release points for a detailed discussion. Here are the locations of Chapman’s fastballs when they were 53 feet from the plate, an estimate of release point.

It looks like he is releasing his fastballs about six inches higher and closer to the center of the mound: so more over-the-top and less 3/4 delivery. Again this conclusion is hard to make without the actual release point, and because the Pitch F/x system is more noisy at the release-point end of the trajectory than the plate-location end. So I wanted to see if I could back it up with photographic support. It was hard to find pictures from the head-on angle, but it does look like he has a slightly more over-the-top delivery in 2011 than in 2010 and definitely more than in 2009 during the World Baseball Classic.

This suggests, though definitely not conclusively, that Chapman may have “lost” his release point. And it is possible that this “lost” release point plays a role in his huge walk rate.




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Dave Allen's other baseball work can be found at Baseball Analysts.


18 Responses to “Diagnosing Aroldis Chapman’s Wildness”

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  1. colin says:

    Pitching coach Price has said it’s release point, that he’s actually coming too far around the ball. See John Fay’s blog

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    • Dave Allen says:

      Interesting thanks for the heads up. Here is what Price said:

      Bryan Price thinks Aroldis Chapman recent problems are mechanical.

      “His arm slot gets too low,” Price said. “He gets across the ball. He’s pulling a lot of balls inside to right-handed hitters.”

      I definitely see lots of balls inside to right-hand hitters, but the arm slot seems high, not low, to me compared to 2010.

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      • TCQ says:

        Diagnosing pitching problems as a drop in arm slot is kind of a pat response for pitching coaches, from what I’ve seen. Never heard someone coached to drop down (except when going full side arm or something, obviously).

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      • Spiggy says:

        TCQ: If I recall, one of the first things Bruce Walton did with Morrow is suggest that he move to a 3/4 slot instead of an over-the-top delivery (though I could be wrong). Though I agree that it often seems used as the default problem.

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      • Colin says:

        I haven’t noticed the arm slot when watching him, just reporting the source. Anecdotally he seems to struggle when entering the game with runners on base (though that wasn’t the case last time out) and when he pitches more than back-to-back days. Seems like a guy who’s destined to start because of the repeat days problems and the fact that when he’s on he wipes out every hitter who steps to the plate. Rarely has problems with one batter and adjusts to the rest of them. Either he’s on or he’s not, but when he has it down that day-look out.

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  2. reillocity says:

    I beg to differ, stathead. It’s far more likely that Chapman’s been cursed for destroying the pinata filled with digestive juices when he filmed that Pepto Bismol “Cinco de Mayo” spot back in spring training (see NotGraphs entry from May 5 for indisputable video evidence … and slow-mo footage of his pitching mechanics).

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  3. Jimbo says:

    Chapman actually isn’t that good. Read the stuff written by Peter Bjarkman, who knows pretty much everything about Cuban baseball, about Chapman. He’s nowhere close to being the most talented Cuban player, let alone the best player to ever defect from Fidelistan.

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    • Yirmiyahu says:

      This comment actually isn’t that good. I read that on some blog.

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    • DCN says:

      Yeah no shit he’s not the best Cuban player. He’s a pitcher with amazing speed and a lot of upside. What else has anybody been saying about him?

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    • DavidCEisen says:

      Apparently being a good Cuban baseball player is like being the highlander: There can only be one.

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  4. cs3 says:

    Would a change in the location of a pitchers foot on the rubber have a similar effect?
    In the top set of diagrams, the spray pattern looks pretty much the same, but its just shifted about 6-8 inches towards the inside part of the plate (to RHB)

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  5. stefangfg says:

    Will Carroll had this to say about Aroldis on May 6: “Remember what I said about proprioception and control issues earlier? Aroldis Chapman is having control issues suddenly.” The wildness streak may be a symptom of an underlying injury. More Carroll: “Proprioception is the body’s ability to locate itself in space. You can close your eyes and still know where your arms are at if you move them because of proprioception. When this is broken, there’s some sort of neuromuscular issue, often a breakdown in the way a joint is functioning due to an instability”

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  6. CircleChange11 says:

    This is where “going to video” would be most helpful.

    When the control is consistently “off” like his is, it’s been my experience, it’s a timing issue. Specifically when the pitcher’s stride foot makes contact the pitching arm (forearm) is not vertical (perpindicular) to the ground … and the pitches result higher and ‘awayer’ than what they were aiming for. Simplest fix is to “slow up the front side (so the arm can catch up.

    It throws off the rotation of the trunk, and can also lead the the glove arm side being further from the body which brings in the cliche … wait for it … “flying open”.

    When you’re “all arms and legs” like Chapman is, this can happen … especially when pitching in relief with fewer pitches to get your rhthum. Pitching in relief could also lead to “rushing” (described above) by trying to get everything to the plate quicker due to adrenaline or trying to throw harder.

    Video would be more telling than anything. You’d be able to see: setup, arm action, rotation, timing, and lastly release point.

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  7. MGL says:

    “Obviously these are tiny samples of innings, but going from three walks per nine to over 11 is alarming.”

    When you are looking at 2 tiny samples of data, there is no “going from one to another.” That would be like wondering why I went from 8 heads and 2 tails in my first 10 flips to 7 tails and 3 heads in my second 10 flips.

    Now, if you want to discuss why he has been so wild in his first 27 2/3 IP of MLB baseball (24 BB+HP), that’s fine. But to characterize the “problem” as going from 5 walks in 15 innings to 16 walks in 13 innings is just silly. There is barely any functional difference between the two.

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  8. Antonio Bananas says:

    So many things have to go right mechanically to even throw the ball 137.5 MPH or whatever the stadium gun clocked him at recently. Much less throwing it accurately. I’m never impressed with flame throwers. I’d rather have a guy with a solid fastball/change/cutter with pinpoint control and smarts. Arm speed slows down with age, guys learn how to hit the velocity, but smart control guys last.

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    • CircleChange11 says:

      [1] I think the record books indicate that batters do NOT learn how to hit extreme velocity pitchers. Batters didn’t learn to hit JR Richard, Bob Feller, Randy Johnson, Nolan Ryan, or Rob Dibble. Ryan and Johnson had major control problems early in their careers as well. You can improve accuracy to varying degrees. You can’t practice yourself or teach someone to throw 105 mph. It’s the most rare attribute in baseball.

      [2] The number of pitchers with master control with decent velocity is small. I think many teams would love to have more guys that were control specialists.

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  9. stefangfg says:

    Aroldis on the DL now due to a recurrence of shoulder inflammation. See my comments above; looks like Will Carroll nailed this one. Probably some tendon or ligament damage underlying the inflammation. Wouldn’t be surprised if a need for surgery arises.

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