What Cole Hamels Is Doing Differently

Cole Hamels has not looked like himself this year. After ERAs of 3.06, 2.79, and 3.05 from 2010 through 2012, Hamels now has a 4.61 ERA nine starts into this season. By itself, that doesn’t mean he’s doing anything wrong. Pitchers are vulnerable to random fluctuations and luck in nine — or even in 30 — starts. For example, take the Hamels from 2009: After the left-hander finished 2008 with a 3.09 ERA and a World Series MVP trophy, expectations were high for the next season. But Hamels fell by the wayside and posted a 4.32 ERA, even though his walk, strikeout, and ground ball numbers were all in the normal range for him.

His DIPS numbers suggested that there wasn’t anything really wrong with Hamels then, and that with a little bit of patience, he would go back to dominating hitters as he had previously. In 2010, that suggestion came to fruition, and Hamels went right back to being one of the game’s premier left-handed starters.

Fast forward to 2013, and Hamels ERA is up once again. However, this time, something does look different. Look at his walk rate, his strikeout rate, his SIERA and his ERA in the past six years:

Year K% BB% SIERA ERA
2008 21.4 5.8 3.64 3.09
2009 20.6 5.3 3.66 4.32
2010 24.7 7.1 3.26 3.06
2011 22.8 5.2 3.03 2.79
2012 24.9 6.0 3.22 3.05
2013 19.5 10.0 4.35 4.61

Unlike in 2009, the spike in ERA is matched by his peripherals— his SIERA is similar to his ERA. The reason is simple — he’s walking a lot more batters and striking out fewer of them. That can be a change in talent level, and it may actually be. But it could also be that he or hitters have changed in some way, and that a game theoretic approach might be better. In other words, it could be that he — or the hitters he faces — have adjusted their strategy and he needs to evolve.

The first thing I always check to determine whether a pitcher’s talent level has changed (or if he’s hurt, etc.) is his velocity. That has been shown time and again to be a somehow underrated aspect of pitching skill. As shown on the table below, that’s not the problem at all — not on any of his pitches.

Year Fastball Velo Changeup Velo Cutter Velo Curveball Velo
2010 91.7 82.1 88.5 76.4
2011 91.2 83.4 88.5 76.2
2012 90.9 83.9 88.1 75.7
2013 91.3 83.3 87.9 75.4

The velocities are similar year to year. But what about movement?

Year Fastball x-Mov Changeup x-mov Cutter x-mov Curveball x-mov
2010 3.9 7.8 -0.8 -1.6
2011 4.0 8.4 -0.7 -1.4
2012 4.8 8.5 -0.7 -1.8
2013 4.8 8.4 -0.1 -1.7
Year Fastball z-Mov Changeup z-mov Cutter z-mov Curveball z-mov
2010 11.5 6.7 7.0 -3.2
2011 10.9 6.0 7.2 -3.5
2012 10.8 6.7 7.2 -4.2
2013 11.5 6.9 7.4 -3.8

That has not changed, either. So it looks like each of Hamels’ individual pitches is about the same. And what about the performances on those pitches? A common approach is to look at the run values on each pitch (normalized on a per-100-pitch basis), and you can start to see where Hamels is begins to see his results differ:

Year vFA/C vCH/C vFC/C vCU/C
2010 0.53 0.77 -0.49 0.27
2011 0.05 3.73 2.27 -0.27
2012 0.38 1.04 -0.32 1.63
2013 -2.01 2.81 -1.53 1.86

This makes it look like the main drop in performance has come on Hamels’ fastballs. But as I explained in my research on game theory and pitch selection, these numbers are misleading because they don’t consider the actual count in which the pitches were thrown.

Unsurprisingly, Hamels tends to throws fastballs when he’s behind the count so all this is tells us is he’s walking more people — which we knew already. Instead, we need to look at things more deeply. Ideally, I would have had performance per plate appearance by pitch thrown in each count. Still, without that data, I was able to detect a likely issue.

Let’s take an extra step and look at the walks and strikeouts by pitch type:

Year FB K% FB BB% CH K% CH BB% FC K% FC BB% CU K% CU BB%
2010 19.3 8.1 34.8 5.7 29.3 2.4 25.5 0.0
2011 13.8 6.5 35.1 4.4 19.1 2.6 44.8 0.0
2012 14.6 6.8 36.9 5.2 13.0 5.2 47.0 0.0
2013 11.5 12.3 35.6 11.9 13.9 0.0 37.5 0.0

This makes it look like he’s walking more batters on his changeup and fastball, but is he actually throwing them for fewer strikes?

Year Fastball Strike% Changeup Strike% Cutter Strike% Curveball Strike%
2010 67.0 70.8 62.8 52.8
2011 65.7 72.0 66.8 50.5
2012 66.5 72.2 62.3 53.7
2013 64.3 62.6 65.4 55.9

Look where the biggest dropoff happens: changeup strike percent is way down. If you look at a few other peripherals, it’s clear the issue is he’s throwing fewer pitches in the zone. Although he’s striking out fewer hitters, it doesn’t seem to be associated with a major change in contact percent:

Year Zone% O-Contact% Z-Contact% O-Swing% Z-Swing%
2010 50.8 55.1 83.8 30.9 64.2
2011 52.1 56.7 84.4 31.4 61.5
2012 48.4 58.0 82.4 34.3 64.9
2013 46.4 58.7 85.8 33.8 64.3

Since we know he’s throwing fewer pitches in the zone this year — and that’s leading to the change in his walks and his strikeouts — we can now break that down further by pitch type:

Year Fastball Zone% Changeup Zone% Cutter Zone% Curveball Zone%
2010 56.0 44.1 46.2 40.8
2011 58.0 45.6 54.7 35.9
2012 54.8 42.0 45.3 36.7
2013 54.6 30.6 50.9 35.6

The obvious difference seems to be showing up on change-ups. Is that because of some difference in contact rate or swing rate?

Year Changeup Swing% Changeup Contact% Changeup O-Swing% Changeup O-Contact% Changeup Z-Swing% Changeup Z-Contact
2010 58.5 53.3 49.1 38.7 69.1 66.3
2011 58.8 54.0 48.6 39.7 71.0 65.6
2012 60.1 54.3 48.5 40.2 76.0 66.8
2013 53.2 50.4 46.0 42.7 69.4 62.0

Hitters seem to be responding rather similarly to Hamels’ changeups when they are in the strike zone, as in previous years. Hitters are also responding to Hamels’ changeups when they’re out of the strike zone. It’s just that he is throwing it out of the zone more. This puts him further behind in the count, and allows hitters to be more selective and draw walks, all while driving down Hamels’ strikeout rate.

This leaves open the question of whether Hamels can actually change that and throw more changeups for strikes. It may be that his talent has deteriorated such that he can’t locate his changeup as well, but more likely, this is a temporary issue. Hamels knows that falling behind hitters isn’t working, and his track record suggests that he is capable of throwing the pitch for strikes. If he can get back to throwing the change-up in the zone with more frequency, hitters will chase more often when he buries it out of the zone, and he should get back to being the dominating left-hander he’s been for most of his career.




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Matt writes for FanGraphs and The Hardball Times, and models arbitration salaries for MLB Trade Rumors. Follow him on Twitter @Matt_Swa.


16 Responses to “What Cole Hamels Is Doing Differently”

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  1. louielips3 says:

    This was a very interesting analysis. Well done.

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  2. Joe Peta says:

    Brilliant scouting work, Matt. I can’t even think of a probing follow-up question.

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  3. t says:

    One of the big topics of discussion in Philly has been his pitch selection. There was a lot of speculation if Ruiz being out had an effect on that. He’s throwing a lot more cutters (17.3% vs 9.1% last year) and less changeups.

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  4. Colonel Angus says:

    Wow I hate cutters…the delusion of grandeur that they can throw it like Mo is just silly. Brandon Morrow is another guy with great stuff that has been sucked into the cutter vortex recently ugh.

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    • Rob says:

      I’ve got nothing against the cutter, but I did watch Kenley Jansen throw 9 in a row against the Braves on Saturday. The 8th and 9th cutters were put in the left field stands by Evan Gattis and Andrelton Simmons. It can be a great pitch, but you generally have to have SOMETHING else. (FWIW, Rivera also throws a 4-seamer and 2-seamer….not as much a “one-pitch” guy as he’s made out to be.)

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    • 4233 says:

      Don’t forget Jon Lester too…..Game against the twinkies tonight just serving em up…..

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  5. justaname says:

    It could also be that Hamels is tipping his changeup, therefore hitter are more likely to take the pitch for a ball, rather than swinging and missing.

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  6. justaname says:

    I don’t think pitchers generally want to throw a changeup in the strike zone – an effective changeup will usually end up down, out of the zone. Therefore, the disguising of a changeup as a fastball is more important than whether it is thrown for a strike.

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    • Richard says:

      And yet presumably you noticed the nice tables Matt provided showing how more often Hamels was throwing his changeup for strikes before this year.

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      • justaname says:

        I probably could have tried to comprehend the data more thoroughly first, and I admit to not understanding the walks and strikeouts by pitch type table. Does this represent the percent outcome on all counts? Matt’s work is undeniably excellent, yet it is oversimplifying the problem by saying Hamels just needs to throw more changeups for strikes. This analysis assumes that all pitches in the strike zone are equal and all pitches out of the zone are equal. The data show that Hamels has had a precipitous drop in strikeouts with the fastball and corresponding increase in fastball walks (just about equal in result % of changeup walks). I would argue that fastball command to set up the change is equally important.

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  7. Word says:

    This is great work, Matt.

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  8. fantasysportshawk says:

    Top notch analysis….top notch.

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  9. PillsburyFlowboy says:

    Excellent work, Matt. If I might suggest one thing, perhaps as a follow-up, a piece examining what caused his problems in 2009 might lend some insight into whether or not his current issues can be corrected. His run from 2010-2012 was phenomenal, so if you were to uncover a similar underlying issue in his 2009 performance it may indicate that he made some sort of adjustments and would presumably be capable of doing it again. And once again, I can’t stress how awesome and in-depth this analysis was.

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  10. Dave says:

    Nice — any difference on the other side of the battery — is Ruiz better at framing than Kratz?

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  11. Matty Brown says:

    This was a wonderful example, or template if you will, for a pitcher performance case study. I felt like I was in a class, except i enjoyed it.

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