Mid-season Arsenal Scores

About a month ago, I started searching for the league’s underthrown pitches. Pitches that despite inducing elite swing-and-miss, ground ball, and pop-up rates, are thrown with scarcity relative to other inferior offerings. It was as an enlightening a topic to research, as it dealt with untapped potential, as it was a fun series to write. Though to be honest, there wasn’t a whole lot of actionable fantasy advice to be gleamed. But in the process of writing those pieces, I had to grade each pitch. And arsenal scores, a subject of interest to the RotoGraphs community over the years, were just a stone’s throw from away from the groundwork I’d already laid.

The pitch grades I used were comprised of three components converted into Z-Scores: whiffs, ground balls plus pop-ups, and called strike-to-ball ratio. To each Z-Score, I applied weights (below) based off a linear model and summed them to arrive at an overall Arsenal Score. I’ve provided two sets of results, one in which each pitch is weighted evenly and another that weights each offering based on frequency thrown. I’ve pretty much taken the work that Eno and Alex had done previously, added an element of control, and refined the weighting based on a correlation between the aforementioned components and Baseball Prospectus’ True Average.

Correlations to True Average
Attribute Coefficient P-Value Adjusted Z-Score Weights
Whiffs per Swing -0.35786 1.97E-14 0.533
(GB + PU)/BIP -0.17683 8.05E-07 0.263
Called S/B -0.13675 3.18E-05 0.204
R2 = .3592

While there are strong correlations between the outcomes evaluated (whiffs, ground balls, pop-ups, and called strikes), there is still a significant amount of the variation left unaccounted for. Perhaps, not unrelated, we’re still at the point where we depend on outcomes to evaluate pitches, relying on hitters’ decisions and talents instead of an offering’s innate qualities alone.  These are some of the drawbacks with this methodology.

One other thing before we look into a few of the interesting names to make the list: it’s too exhausting to keep scraping the PitchF/x leaderboards for each article so this data is, admittedly, a week old. The table below doesn’t account for Clayton Kershaw’s recent outing against the Diamondbacks during which he struck out 11 nor does it include Jon Gray’s latest turns since his activation, though in fairness Gray still would fall short of the 50 pitch threshold on half his repertoire.

Still, in the never-ending quest to separate talent from results, this is a helpful exercise and one that I hope you can find use for.

Top 150 Arsenals
Player 4-Sm Sinker Cutter Curve Slider Change Pitches Rk Unweighted Arsenal wRk Frequency-weighted Arsenal
Jacob deGrom 1.875 1.111 0.601 0.134 0.369 5 2 4.090 1 1.070
Alex Wood 1.450 0.693 0.528 3 8 2.672 2 1.023
Dallas Keuchel 1.305 0.012 1.214 0.437 4 4 2.968 3 0.901
Robbie Ray 1.226 -0.096 1.031 0.100 4 12 2.260 4 0.898
James Paxton 1.146 0.332 0.646 3 14 2.124 5 0.881
Brandon Finnegan 2.742 1 6 2.742 6 0.854
Trevor Cahill 0.591 1.250 1.204 1.052 4 1 4.096 7 0.842
Sean Manaea 0.562 0.617 1.324 3 9 2.502 8 0.760
Chris Sale 0.766 0.579 0.381 1.127 4 5 2.852 9 0.707
Corey Kluber -0.306 1.774 1.238 1.162 4 3 3.868 10 0.672
Max Scherzer 0.406 -0.799 1.567 0.928 4 15 2.101 11 0.660
Jose Berrios 1.555 -0.041 0.115 -0.497 4 37 1.132 12 0.611
Carlos Martinez 0.283 0.753 0.804 0.184 4 19 2.024 13 0.553
Sonny Gray 0.429 1.573 -0.093 0.454 -0.430 5 21 1.933 14 0.549
Zack Greinke 0.450 0.370 0.884 0.722 0.306 5 7 2.732 15 0.534
Danny Salazar 0.734 -0.457 -0.063 1.031 0.810 5 17 2.054 16 0.523
Noah Syndergaard 0.258 0.880 1.237 3 11 2.376 17 0.521
Marcus Stroman 0.822 0.790 0.066 0.084 4 22 1.762 18 0.510
Jaime Garcia 0.071 0.954 0.196 -0.196 1.157 5 13 2.181 19 0.506
Jameson Taillon 0.455 1.153 0.068 -1.002 4 65 0.674 20 0.506
Taijuan Walker 1.046 -0.245 -0.493 3 87 0.308 21 0.504
Lance Lynn 0.578 0.691 0.342 -1.014 4 70 0.597 22 0.501
Jimmy Nelson 0.570 0.825 0.786 -0.751 4 30 1.430 23 0.481
Stephen Strasburg 0.124 1.284 -1.476 1.343 4 33 1.275 24 0.478
Luis Severino 0.583 0.457 -0.029 3 44 1.011 25 0.472
Jacob Faria 0.590 -0.122 1.145 3 25 1.613 26 0.463
Lance McCullers 0.084 0.293 0.660 0.289 4 32 1.327 27 0.420
Zack Godley 0.030 -0.108 0.969 1.192 4 16 2.084 28 0.415
Kendall Graveman 0.615 -0.175 -0.487 3 111 -0.047 29 0.395
Luis Perdomo 0.126 0.901 2 42 1.027 30 0.372
Doug Fister 0.545 1 71 0.545 31 0.365
Daniel Gossett 0.552 1.096 2 24 1.648 32 0.364
Trevor Williams 0.481 1.328 -0.630 -0.293 4 53 0.887 33 0.363
Tyler Skaggs 0.494 0.231 2 60 0.725 34 0.361
Alex Meyer 0.574 -0.554 0.855 3 54 0.875 35 0.355
Aaron Nola 0.509 0.000 0.274 0.799 4 26 1.582 36 0.351
Vincent Velasquez 0.725 -0.510 -0.190 -0.736 4 153 -0.711 37 0.348
Clayton Kershaw 0.235 0.272 0.579 3 39 1.087 38 0.348
Hyun-jin Ryu 0.322 0.489 0.605 0.140 4 27 1.555 39 0.339
Michael Wacha 0.541 -0.031 0.210 0.177 4 52 0.897 40 0.335
Chad Kuhl 0.216 0.998 -0.357 3 56 0.858 41 0.332
Randall Delgado 0.613 0.385 0.677 3 23 1.675 42 0.324
J.A. Happ 0.649 0.397 -0.721 -0.197 4 95 0.128 43 0.321
Michael Pineda 0.294 0.606 -0.471 3 79 0.429 44 0.317
Brad Peacock -0.553 0.981 2 80 0.428 45 0.308
Charlie Morton 0.026 0.484 0.875 3 31 1.385 46 0.300
Dan Straily 0.466 0.235 -0.003 3 63 0.698 47 0.297
Brandon McCarthy 1.110 -0.120 -0.013 3 45 0.978 48 0.296
Mat Latos 1.019 1 43 1.019 49 0.287
Kenta Maeda 0.052 0.687 0.094 0.598 0.618 -0.073 6 20 1.975 50 0.278
Eduardo Rodriguez 0.314 -0.069 0.373 3 68 0.619 51 0.270
Jon Lester -0.027 0.688 0.266 0.649 0.465 5 18 2.042 52 0.268
Rich Hill 0.845 -0.381 2 78 0.464 53 0.264
David Price 0.504 0.311 0.247 3 40 1.062 54 0.262
Tim Adleman 0.579 -0.574 1.094 0.030 4 38 1.129 55 0.257
Aaron Sanchez 0.633 -0.353 2 90 0.280 56 0.255
Jake Arrieta 0.450 0.773 -0.721 -0.233 4 91 0.270 57 0.254
Carlos Carrasco -0.519 -0.110 1.085 0.958 0.998 5 10 2.412 58 0.244
Tyler Chatwood 0.256 0.300 0.046 0.056 0.882 5 28 1.541 59 0.237
Joe Biagini 0.424 -0.808 0.595 -0.139 4 101 0.072 60 0.235
Rookie Davis 0.705 -0.903 0.051 3 118 -0.148 61 0.232
Jeff Hoffman 0.064 0.636 0.751 3 29 1.451 62 0.230
Yu Darvish 0.526 0.120 0.394 0.065 -0.130 5 46 0.975 63 0.224
Chase Anderson 0.421 -0.161 -0.387 0.535 0.446 5 57 0.854 64 0.223
Michael Fulmer 0.245 0.256 -0.468 0.895 4 50 0.927 65 0.222
Casey Lawrence 0.484 1 75 0.484 66 0.219
Jordan Montgomery -0.493 0.276 1.208 -0.021 -0.048 5 51 0.922 67 0.219
Jake Junis -0.153 0.172 0.953 3 47 0.972 68 0.216
Mike Clevinger 0.017 0.111 0.739 0.347 4 36 1.213 69 0.210
Mike Fiers 0.809 -0.030 -0.479 0.054 -0.729 0.493 6 96 0.119 70 0.210
Jeff Samardzija 0.462 0.214 0.191 0.400 -0.036 5 35 1.232 71 0.209
Jose Quintana 0.278 -0.246 0.328 0.506 4 55 0.866 72 0.205
Lisalverto Bonilla 0.371 0.358 2 59 0.729 73 0.192
Junior Guerra 0.457 -0.053 -0.136 3 92 0.268 74 0.183
Madison Bumgarner -0.095 0.471 0.582 3 49 0.958 75 0.182
Drew Pomeranz 0.239 0.994 0.010 3 34 1.242 76 0.182
Kyle Hendricks 0.514 0.360 -1.934 -0.028 4 167 -1.087 77 0.173
Rafael Montero 0.697 1 64 0.697 78 0.167
Andrew Triggs 0.646 -0.256 -0.148 3 93 0.242 79 0.162
Chris Archer 0.028 0.283 0.214 3 72 0.525 80 0.158
Jhoulys Chacin -0.097 0.790 0.537 -1.293 4 113 -0.063 81 0.135
Buck Farmer 0.642 1 67 0.642 82 0.134
Joe Musgrove 0.509 0.252 0.435 -0.452 -0.127 5 69 0.618 83 0.124
Matt Andriese 0.209 -0.285 -0.222 0.318 4 106 0.020 84 0.111
Gio Gonzalez -0.091 -0.224 0.637 0.330 4 66 0.653 85 0.107
James Shields 0.060 0.461 2 73 0.521 86 0.103
Sean Newcomb 0.415 1 81 0.415 87 0.100
Trevor Bauer 0.040 -0.349 0.457 0.325 -0.161 5 86 0.312 88 0.099
A.J. Griffin 0.147 0.196 -0.302 3 104 0.041 89 0.098
Luis Cessa 0.297 1 88 0.297 90 0.095
Edinson Volquez -0.047 -0.174 0.540 3 85 0.319 91 0.087
Alec Asher 0.714 -1.289 0.643 3 102 0.069 92 0.085
Shelby Miller 0.108 0.566 -0.744 3 114 -0.070 93 0.082
Johnny Cueto -0.530 0.247 0.458 -0.287 0.590 5 76 0.477 94 0.078
Clayton Richard 0.348 -0.220 -0.581 3 133 -0.453 95 0.074
Nate Karns -0.463 -1.169 0.863 0.216 4 137 -0.553 96 0.070
Tyler Anderson -0.311 0.504 0.308 3 74 0.500 97 0.068
Ian Kennedy -0.079 0.371 0.076 0.381 4 58 0.749 98 0.057
Francisco Liriano -0.511 0.695 0.190 3 84 0.374 99 0.054
Marco Estrada 0.149 -0.841 -0.645 0.244 4 168 -1.093 100 0.052
CC Sabathia 0.410 -0.349 -0.172 0.517 4 83 0.406 101 0.047
Jharel Cotton 0.109 -0.501 0.705 -0.780 -0.180 5 148 -0.646 102 0.039
Erasmo Ramirez 0.449 -0.135 -0.241 3 100 0.073 103 0.035
Justin Nicolino 0.086 0.011 2 97 0.097 104 0.035
Nik Turley 0.085 1 99 0.085 105 0.028
Jacob Turner 0.035 1 105 0.035 106 0.021
Jake Odorizzi 0.324 -0.557 -1.052 3 177 -1.284 107 0.020
Zack Wheeler 0.109 0.501 -0.781 -0.252 0.398 5 109 -0.026 108 0.018
Blake Snell -0.314 0.365 0.803 0.179 4 41 1.032 109 0.012
Mike Pelfrey -0.157 1.435 -0.803 3 77 0.476 110 0.007
Jason Vargas 0.001 -0.485 -0.287 0.602 4 120 -0.169 111 0.007
Tommy Milone 0.459 -0.330 -0.080 3 103 0.049 112 0.005
Ben Lively 1.107 -1.182 -0.475 3 136 -0.550 113 0.005
J.C. Ramirez -0.167 0.340 0.025 3 94 0.198 114 0.003
Mike Montgomery -0.113 0.115 2 107 0.002 115 0.000
R.A. Dickey -0.077 1 115 -0.077 116 -0.008
Masahiro Tanaka -0.310 -0.540 0.534 0.272 4 110 -0.044 117 -0.011
Brian Johnson 0.097 -0.250 2 119 -0.153 118 -0.013
John Lackey 0.404 -0.308 -0.466 -0.205 -0.597 5 170 -1.172 119 -0.014
Gerrit Cole 0.217 -0.440 -0.550 0.322 -0.104 5 138 -0.556 120 -0.016
Kyle Freeland -0.137 0.119 0.175 -0.257 -0.607 5 150 -0.706 121 -0.016
Dinelson Lamet -0.459 0.486 0.384 3 82 0.411 122 -0.016
Chase DeJong -0.106 1 116 -0.106 123 -0.016
Ty Blach 0.304 -0.979 -1.469 -0.095 4 199 -2.239 124 -0.019
Francis Martes -0.052 1 112 -0.052 125 -0.020
Danny Duffy -0.589 0.312 0.058 0.306 4 98 0.088 126 -0.023
Adam Conley -0.307 0.399 0.609 3 61 0.701 127 -0.043
Patrick Corbin -0.461 -0.598 0.861 -0.450 4 149 -0.648 128 -0.047
Ariel Miranda -0.243 0.830 0.378 3 48 0.964 129 -0.054
Rick Porcello 0.156 -0.208 0.733 -0.563 -0.340 0.096 6 117 -0.127 130 -0.055
Austin Bibens-Dirkx 0.426 -1.055 -0.281 3 160 -0.909 131 -0.064
Parker Bridwell -0.252 1 123 -0.252 132 -0.065
Wei-Yin Chen -0.082 -0.495 0.283 3 126 -0.295 133 -0.072
Matt Harvey -0.021 0.695 0.452 -0.450 -0.379 5 89 0.297 134 -0.075
Wade Miley -0.713 0.218 0.024 0.012 0.193 5 124 -0.268 135 -0.077
Alex Cobb -0.373 0.159 2 122 -0.214 136 -0.101
Julio Teheran 0.071 -0.244 -0.096 0.056 -0.990 5 172 -1.203 137 -0.105
Braden Shipley -0.384 1 130 -0.384 138 -0.108
Daniel Norris -0.411 0.667 -0.129 0.573 4 62 0.700 139 -0.114
Asher Wojciechowski -0.536 1 135 -0.536 140 -0.118
Felix Hernandez -0.934 0.435 -0.069 3 140 -0.568 141 -0.121
Yovani Gallardo -0.025 0.288 -0.370 -0.320 -0.394 5 155 -0.820 142 -0.122
Jeff Locke -1.170 -0.346 1.172 3 129 -0.344 143 -0.122
Scott Feldman 0.088 -0.199 -0.257 -0.341 4 151 -0.709 144 -0.124
Mike Foltynewicz -0.072 -0.314 -0.029 -0.121 0.123 5 131 -0.413 145 -0.124
Hisashi Iwakuma -0.319 -0.240 2 139 -0.560 146 -0.138
Antonio Senzatela -0.048 -0.504 -0.030 3 142 -0.581 147 -0.139
Ervin Santana -0.460 -0.040 0.345 -0.477 4 146 -0.632 148 -0.142
Kyle Kendrick -0.313 1 128 -0.313 149 -0.148
German Marquez -0.294 0.335 -0.631 3 143 -0.590 150 -0.150

Noteworthy Arsenals

Alex Wood – at some point I need to stop being surprised by Alex Wood. Since the start of last season, he’s thrown 141 innings with a 2.55 ERA, 2.53 FIP, and 2.88 xFIP on the back of funky deception and three above average pitches. This season, Wood features the league’s 3rd best sinker, 17th best curve, and 25th best changeup.

Always one to generate ground balls, he’s now doing so at a near league-leading clip. And the whiffs? Well, he’s first on the Dodgers in strikeout rate, which should tell you all you need to know. And going back one year, Wood’s K-BB% ranks 10th in the league among starters who’ve thrown as many innings. As long as he stays healthy, Alex Wood is as good as any.

Robbie Ray – I have to admit, I’m still not aboard the Robbie Ray Train. I’ve never been able to get past his command and homer problems. But to be fair, neither has he. Ray is walking more batters and inducing fewer ground balls than ever before. And there doesn’t there seem to be an easy fix tinkering with his pitch mix either. His two most underthrown pitches are his four-seamer, which is merely average at generating grounders, and his curveball which he actually throws fairly often; it’s considered underthrown not because he throws it less frequently than the average pitcher does but because it’s so effective, he should throw it as often as possible.

Perhaps Ray has found a way to manage elevated contact but with an average Fly Ball and Line Drive Exit Velocity in the 75th percentile (in this case, high is bad), I’m not too eager to wait around to find out. Ray’s elite arsenal score is supported almost entirely by incredible swing-and-miss and stuff, which undeniably has value. And perhaps, in this inflated offensive environment, you can stomach an ERA more in line with his FIP or xFIP. Just don’t be surprised to see a sharp ERA correction in the second half. Ray should net a haul in return. Those with pitching to spare, and I realize there are just a handful of you, might consider selling high.

Lance Lynn – despite his placement on this list, I’d caution against buying Lynn. His fastball and sinker velocity dropped precipitously a few starts ago starts and though it returned in his last outing, he’s the unlucky protagonist in a long and storied injury history. So while those two games may prove nothing more than a blip, I’m still concerned enough to wait and see.

Jimmy Nelson – if you haven’t already, I’d suggest listening to this latest episode of The Sleeper and the Bust. Paul and Eno do a great job of analyzing changes to Nelson’s breaking pitches that explain his unforeseen success (sincere apologies to anyone who foresaw said success but I know you’re lying so, I forgive you). After being inexplicably cut in one of my Ottoneu leagues a few weeks ago, I’ve been riding him ever since. Nelson’s post-hype breakout has been one of the truly rewarding stories in this pitching-starved environment.

Clayton Kershaw – a commenter last week pointed out that Kershaw was too low on this list. How could I argue otherwise? I mean, I tried but I admit I felt silly doing so. This is one of the limitations with any purely quantitative framework – some results just don’t pass the smell test. That doesn’t mean your whole model sucks, just that you need to buttress your numbers with some common sense. But as I pointed out in my response, as good as Kershaw has been, he hasn’t been the same Kershaw to which we’ve grown accustomed. This isn’t a knock nor is it to say he won’t “turn things around.” And yes, I recognize how ridiculous I sound, hence the “air” quotes that actually aren’t “air” quotes because they appear on the screen in front of you.

But we’re looking at Kershaw’s lowest strikeout rate, K-BB%, and whiff rate since 2013 and his lowest ground ball rate since 2011. And the homers are alarming. Hitters are averaging 1.24 bombs per nine innings off Kershaw; not only is that significantly above the league average, it’s nearly 150% higher than his career rate through last season. Check out Jeff Sullivan’s piece on this very issue here.

Now, that doesn’t tell the whole tale. Obviously. When it comes to contact management, Kershaw is on the right side of average for most Statcast metrics and most everything else. Honestly, talking about Kershaw’s arsenal is a waste of time. He’s extraordinary. I single him out for no other reason than to illustrate the limitations of scoring arsenals based on just a handful of outcomes. But since you came here for fantasy advice, here it is: for anyone playing in the 1% of Yahoo! leagues where Clayton Kershaw is available, consider picking him up. I’d even burn a high waiver priority to do so.

Most Underowned Arsenal

Trevor Cahill is groin-grabbingly underowned. I’ve mentioned him here for his slider and again here for his entire arsenal. In his first start back from a shoulder injury, Cahill tossed 4.1 shutout innings, striking out four and inducing grounders on 82% of the balls Cleveland hitters put in play. Vintage 2017 Cahill. No, he didn’t dominate but he was likely on a strict pitch count and facing one of the league’s hottest lineups. Still available in 78% of Yahoo! leagues, PICK HIM UP.

On another note, this is my last article at RotoGraphs, at least for a while. I’m moving onto other things and as much as I love writing here, I can no longer put in the requisite time to churn out pieces capable of satiating the voracious analytic appetites of this site’s devoted and discerning readership. It’s been a blast and a truly cromulent honor to contribute to my favorite website for the past two years. Hopefully, I get to do so again soon. Thanks for the positive comments and for keeping me honest when I deserved it.

We hoped you liked reading Mid-season Arsenal Scores by Rylan Edwards!

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Rylan writes for Fangraphs and The Hardball Times. Look for his weekly Deep League Waiver Wire and The Chacon Zone columns this season.

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Snerd
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Snerd

Love the work, Rylan. It would be useful to add ranking numbers as well so we don’t have to manually count each pitcher.