Underthrown Pitches And The Pitchers Who Underthrow Them

Identifying pitching breakouts as they happen can be hard. Anticipating them, even harder. Savvy readers of sites such as this rely on plate discipline metrics, batted ball data, and other indicators designed to tease out luck from results in order to uncover which performances have staying power and which are fleeting. And while we’ve arrived at the point in the season when most pitching rates have stabilized, a simple change in pitch mix can render those indicators obsolete. Think Matt Shoemaker and his splitter, Jake Arrieta and his cutter, Max Scherzer and his curveball, or Sonny Gray and his slider.

If you can spot a pitcher pulling unexpected arrows from his quiver as he does it, then cheers to you. But it’s difficult to do that at scale. While trying to anticipate a change in pitch mix before it happens may seem futile at times, doing so is a bet on potential. And what we talk about when we talk about “stuff,” is really potential. One of the components upon which that potential relies, aside from command and health, is an optimal pitch mix.

To identify which pitchers could benefit by throwing their more effective offerings a little more frequently, we have a number of tools at our disposal. Today, we’ll use some of those tools to identify the league’s underthrown four-seam fast balls and sinkers and the pitchers who underthrow them.

First, an explanation of the methodology and one important caveat. I pulled starting pitcher data from Baseball Prospectus’ Pitchf/x leaderboards for all starters meeting the following qualifying minimums:

Qualifying Thresholds
Pitch Minimum pitches
Four-seamer 200
Sinker 50
Cutter 50
Curve 50
Slider 50
Change 50
Splitter 50

Within the seven pitch types, I graded each starter’s offering based on three criteria: whiffs, ground balls, and pop-ups using two metrics, whiffs per swing and ground ball-plus-pop up rate per ball-in-play. I then converted those metrics into Z-Scores and summed them to arrive at a final Pitch Score. And yes, the Pitch Score could be improved by incorporating a measure of control, such as called strike-to-ball ratio or Zone-percentage but that gets tricky on out-pitches or those purposely thrown off the plate; think a spiked curve or anything Dallas Keuchel throws.

To identify which pitches might be underthrown, I used a simple measure of effectiveness-to-frequency, or Pitch Score divided by the percentage a specific pitch is thrown. Let’s call it the Underthrown Index, or UI. For example, according to UI, the most underthrown changeup belongs to Tyler Chatwood, whose changeup’s Pitch Score ranks as the highest in baseball based on whiffs, ground balls, and pop-ups; however, he only throws the pitch 7% of the time. That combination of a highly effective pitch thrown with relative scarcity makes Chatwood’s changeup one of the most underthrown in the game.

UI is not a perfect metric in part because the more infrequently a pitch is thrown (i.e. the smaller the denominator) the larger the UI; in essence it gives priority to small sample sizes. However, having set the threshold at 200 for fastballs and 50 for secondary pitches, we mitigate some of that sample size risk.

Now, analyzing pitches in isolation (i.e. as not part of a larger arsenal) can be misleading. Chatwood’s changeup, or anyone’s for that matter, really only exists in the context of a fastball. Throwing the change too often at the expense of his cheddar negates some of its effectiveness. So when I suggest that Chatwood throw his changeup more often because it appears to be a good pitch, there’s obviously a point at which throwing it too often results in diminishing returns. The point of this analysis isn’t to establish the ideal frequency, though admittedly that’d be awesome. Rather I’m attempting to identify which pitchers may be just a tweak or two away from a more effective mix and perhaps a breakout.

Four-seam Fastballs

Cheese It, Fellas!
Player Number Thrown % 4-Seamer Z-Whf/Sw Z-(GB+PU)/BIP 4-Seam Pitch Score UI
Adam Wainwright 206 23.15% -1.004 3.206 2.201 9.510
Jacob deGrom 444 42.69% 3.855 -0.806 3.048 7.140
Carlos Martinez 268 27.95% 0.656 0.964 1.620 5.796
Kyle Hendricks 206 25.43% 0.122 1.318 1.439 5.659
Michael Fulmer 272 27.67% 0.364 1.200 1.564 5.652
Tyler Chatwood 361 34.35% 0.010 1.790 1.800 5.240
Kyle Freeland 262 29.91% -0.700 2.144 1.444 4.828
Derek Holland 295 29.92% -0.875 2.262 1.387 4.635
Gerrit Cole 385 37.31% 0.700 0.846 1.546 4.143
James Paxton 365 62.50% 2.094 0.492 2.586 4.137
SOURCE: PITCHf/x

Adam Wainwright claims the most underthrown four-seam fastball in baseball. Its ranks 84th out of 102 pitchers in rise, 88th in velocity, and 98th in horizontal movement. It’s slow and straight and hittable, as evidenced by his 12.5% whiff per swing rate, good for 91st among starters. That he tops this leaderboard is what you might consider an odd result. Given however that Wainwright is actually throwing his heater more often than he has at any point in his career, I doubt its effectiveness is as surprising to him as it seems to us.

Wainwright can attribute that effectiveness to some masterful contact management. His four-seamer induces ground balls 71% of the time. That’s 12 percentage points higher than the next guy, over 3.5 standard deviations better than the mean, and most remarkably, 30% higher than his personal career average. There are only 19 other individual pitches in baseball that generate a higher ground ball rate than Waino’s four-seamer; many of those are sinkers, curves, and changes specifically designed to do just that. Going back to 2007, the earliest we have such data, the closest comp is Samuel Deduno, whose four-seamer induced grounders on 68% of balls-in-play in 2012. In other words, Adam Wainwright currently owns the most worm-burningest four-seamer to ever burn worms in the Pitchf/x era.

So what is Wainwright doing differently this year? Looking at his heat maps, it appears he’s challenging lefties down-and-away when historically, he’s been out over the plate against them. Sure enough, locating down-and-away has induced a ton of ground balls. He’s also challenging righties in on the hands, generating similarly elevated four-seam ground ball rates to like-handed batters. Who’d have thought that hitters would have a harder time squaring up balls on the edges of the plate rather than over the heart of it?

To both righties and lefties, Wainwright has become more discerning with his fastball location, which is undeniably a positive development. But does that mean he should throw the pitch more often? Well, given its league leading .000 isolated slugging percentage, I’m inclined to say yes, as long as he continues to locate as stringently as he has been.

It’s now been four years since Wainwright last struck out batters at a better than league average rate. Despite questionable defense behind him, his pinpoint fastball command has seemingly created a powerful ground ball weapon that he’s leaning on more heavily this season. And after having served up the cheddar 31% of the time in a recent start in Colorado, I’m looking forward to seeing the Pitchf/x data from yesterday’s start against the Dodgers.

Other pitchers underthrowing their four-seamers include:

Jacob DeGrom: by whiffs, grounders, and pop-ups, DeGrom has had the best four-seamer in baseball this year. He’s throwing it about 43% of the time, which is league average, so while he could definitely throw it more often, it’s difficult to foresee an extreme surge in frequency. But with a 39% whiff per swing rate, DeGrom’s four-seamer is as whiffy as Wainwright’s is heavy.

Carlos Martinez: throwing his 97 mph four-seamer just 29% of the time, Martinez could certainly throw it more often. However, his pitch mix is extremely well-distributed which may in part elucidate the overall effectiveness of his arsenal. Martinez excels across all three criteria. His four-seam whiffs per swing rate ranks 24th out of 102 pitchers, his ground ball per ball-in-play 35th, and his pop up rate 16th, combining to give him the 8th most effective four-seam fastball among starters.

Kyle Hendricks: after a rough three-start stretch to open the season, Hendriks appears to have righted the ship. While doing so, he’s leaned more heavily on his four-seamer. While poor at generating swings and misses, the pitch has induced a grounder or pop-up in 55% of balls-in-play, the 10th highest frequency in the league among four-seam fastballs.

Sinkers

Underthrown Sinkers
Player Number Thrown % Sinker Z-Whf/Sw Z-(GB+PU)/BIP Sinker Pitch Score UI
Matt Harvey 73 7.72% -0.357 2.553 2.196 28.462
Zack Greinke 80 7.21% 2.442 -0.571 1.871 25.959
Brandon Finnegan 57 31.15% 4.009 2.375 6.384 20.496
Jon Lester 123 11.28% 0.422 1.125 1.547 13.708
Robbie Ray 90 8.94% 0.261 0.947 1.208 13.514
Trevor Williams 63 15.95% 0.771 1.304 2.074 13.004
Jacob deGrom 151 14.52% 2.298 -0.482 1.817 12.513
Carlos Carrasco 57 6.61% 1.692 -0.928 0.765 11.563
Joe Musgrove 94 10.48% -0.288 1.482 1.194 11.397
Eddie Butler 74 29.13% 3.106 0.143 3.250 11.154
SOURCE: PITCHf/x

To read Brooks Baseball’s estimation of Matt Harvey’s sinker, one would understand why he throws it so infrequently:

His sinker is an extreme flyball pitch compared to other pitchers’ sinkers, has less armside run than typical, has little sinking action compared to a true sinker and has slightly above average velo.

Extreme fly ball? Not this year. Yes, its 71% ground ball per ball-in-play merely matches that of Wainwright’s fastball but among the league’s other sinkers, it ranks 8th. It’s as if he traded in those fly balls for grounders yet still found a way to keep the pop-ups, a measure by which the pitch also ranks 8th, by the way. Now, at 10.71% whiffs per swing, it doesn’t induce many misses but maybe that’s not so bad.

Harvey’s sinker has garnered a .083 isolated slugging against, which ranks 23rd out of 126 pitchers. And his .333 slugging against ranks 19th.  It helps that Harvey appears to burying the pitch low and away, often off the plate. It also helps that despite living on the fringes of the zone, it has one of the league’s better called strike-to-ball ratios. And that combination of un-barrelable location and almost perfect proximity to the strike zone, makes the pitch extremely difficult to do anything with.

At 7.7%, Harvey is throwing his sinker more than at any point in his career. While it’s not a sexy out-pitch, using it more often to steal called strikes could indirectly lead to more punch outs. And when hitters do make contact, it’s also a difficult offering to elevate.

Despite going to the well 31% of the time, Brandon Finnegan may also stand to benefit by throwing it more. It’s that good. Its Pitch Score is twice that of the next sinker on the list and it’s elite both in terms of whiffs and grounders, ranking first in both categories.

The average sinker-baller throws the pitch a little under 30% of the time so Finnegan is more or less average in his usage. But leaning on it more heavily at the expense of say, his slider, could do wonders. Then again, why only throw his sinker more? While he’s fallen short of the qualifying four-seamer and changeup thresholds due to injury, both have been excellent to elite this year. Brandon Finnegan, please come back soon.

A complete list of the underthrown four-seamers and sinkers can be found below. I pulled the data on Tuesday morning, 5/29, so it doesn’t reflect any start since then.

Next week, we’ll check out the league’s underthrown cutters and curves.

Underthrown Four-Seamers: The Complete List
Player Number Thrown % 4-Seamer Z-Whf/Sw Z-(GB+PU)/BIP 4-Seam Pitch Score UI
Adam Wainwright 206 23.15% -1.004 3.206 2.201 9.510
Jacob deGrom 444 42.69% 3.855 -0.806 3.048 7.140
Carlos Martinez 268 27.95% 0.656 0.964 1.620 5.796
Kyle Hendricks 206 25.43% 0.122 1.318 1.439 5.659
Michael Fulmer 272 27.67% 0.364 1.200 1.564 5.652
Tyler Chatwood 361 34.35% 0.010 1.790 1.800 5.240
Kyle Freeland 262 29.91% -0.700 2.144 1.444 4.828
Derek Holland 295 29.92% -0.875 2.262 1.387 4.635
Gerrit Cole 385 37.31% 0.700 0.846 1.546 4.143
James Paxton 365 62.50% 2.094 0.492 2.586 4.137
Chris Sale 353 32.96% 2.092 -0.806 1.286 3.901
Robbie Ray 505 50.15% 0.749 1.082 1.831 3.651
Rookie Davis 207 50.74% 0.191 1.554 1.744 3.438
Taijuan Walker 498 56.66% 1.543 0.374 1.917 3.383
Lance Lynn 443 44.93% 2.087 -0.570 1.516 3.375
Danny Salazar 389 39.65% 2.344 -1.042 1.302 3.283
Zack Wheeler 392 42.52% -0.187 1.554 1.367 3.215
Dan Straily 476 53.36% 0.926 0.610 1.536 2.878
Shelby Miller 214 55.73% -0.187 1.790 1.603 2.876
Sean Manaea 374 55.00% 0.072 1.318 1.390 2.527
Rick Porcello 349 30.80% 1.638 -0.924 0.713 2.316
Trevor Williams 214 54.18% -1.108 2.262 1.153 2.129
Vincent Velasquez 589 67.86% 1.074 0.256 1.330 1.959
Ty Blach 412 62.90% -0.796 2.026 1.229 1.954
Gio Gonzalez 388 37.34% 0.090 0.610 0.700 1.875
Yu Darvish 392 34.63% 0.975 -0.334 0.641 1.851
Drew Pomeranz 397 50.51% 0.536 0.374 0.909 1.800
Marco Estrada 547 48.88% 1.295 -0.452 0.842 1.723
Jharel Cotton 216 28.69% 1.036 -0.570 0.465 1.622
Chase Anderson 293 31.85% 1.986 -1.514 0.472 1.482
Clayton Kershaw 534 49.77% -0.437 1.082 0.645 1.296
Luis Severino 469 52.52% 0.718 -0.098 0.620 1.180
Zack Greinke 470 42.34% -0.355 0.846 0.491 1.159
Michael Wacha 372 51.45% 0.782 -0.216 0.566 1.099
Jose Quintana 379 43.31% 0.220 0.256 0.476 1.098
Tyler Skaggs 258 57.72% 0.590 0.020 0.610 1.057
John Lackey 397 41.10% 0.758 -0.334 0.424 1.032
Ariel Miranda 509 58.17% -0.070 0.610 0.540 0.928
Stephen Strasburg 536 54.75% 0.016 0.492 0.507 0.927
Matt Boyd 225 25.11% -0.504 0.728 0.223 0.889
Hyun-jin Ryu 265 44.17% 0.018 0.374 0.391 0.886
Jimmy Nelson 321 35.51% 1.100 -0.806 0.293 0.826
Eduardo Rodriguez 584 63.83% 0.715 -0.334 0.380 0.596
Madison Bumgarner 202 50.37% -0.001 0.256 0.255 0.506
Blake Snell 443 56.43% -0.570 0.728 0.158 0.279
Tim Adleman 242 42.38% 0.999 -0.924 0.075 0.177
Kevin Gausman 684 66.99% -0.313 0.374 0.061 0.091
SOURCE: PITCHf/x

 

Underthrown Sinkers: The Complete List
Player Number Thrown % Sinker Z-Whf/Sw Z-(GB+PU)/BIP Sinker Pitch Score UI
Matt Harvey 73 7.72% -0.357 2.553 2.196 28.462
Zack Greinke 80 7.21% 2.442 -0.571 1.871 25.959
Brandon Finnegan 57 31.15% 4.009 2.375 6.384 20.496
Jon Lester 123 11.28% 0.422 1.125 1.547 13.708
Robbie Ray 90 8.94% 0.261 0.947 1.208 13.514
Trevor Williams 63 15.95% 0.771 1.304 2.074 13.004
Jacob deGrom 151 14.52% 2.298 -0.482 1.817 12.513
Carlos Carrasco 57 6.61% 1.692 -0.928 0.765 11.563
Joe Musgrove 94 10.48% -0.288 1.482 1.194 11.397
Eddie Butler 74 29.13% 3.106 0.143 3.250 11.154
Jaime Garcia 246 28.91% 1.998 1.036 3.034 10.495
Carlos Martinez 277 28.88% 0.199 2.285 2.484 8.601
Sonny Gray 133 27.59% 1.663 0.590 2.253 8.164
Chris Sale 160 14.94% 0.588 0.500 1.088 7.281
Lance Lynn 320 32.45% 1.501 0.857 2.358 7.266
Dallas Keuchel 411 43.54% 1.226 1.928 3.155 7.246
Ervin Santana 164 14.81% 0.296 0.768 1.064 7.181
Brandon McCarthy 193 27.93% 1.005 0.857 1.863 6.669
Jimmy Nelson 294 32.52% 0.986 0.947 1.933 5.943
Jameson Taillon 218 39.78% 1.561 0.590 2.151 5.406
Lance McCullers 225 22.30% 0.232 0.947 1.178 5.285
Alex Wood 335 49.34% 1.031 1.571 2.603 5.275
Erasmo Ramirez 77 30.08% -0.048 1.393 1.345 4.472
CC Sabathia 198 24.66% 0.203 0.768 0.971 3.936
Wily Peralta 219 30.12% -0.414 1.571 1.158 3.843
Andrew Triggs 374 41.14% 0.691 0.768 1.459 3.546
Tommy Milone 62 15.50% 1.083 -0.571 0.512 3.305
Marcus Stroman 599 57.32% 0.344 1.482 1.826 3.186
Matt Garza 125 20.19% 0.185 0.411 0.596 2.953
Aaron Sanchez 186 49.21% 0.741 0.679 1.420 2.886
Tyler Chatwood 296 28.16% 0.833 -0.035 0.797 2.831
Zack Wheeler 199 21.58% 1.247 -0.660 0.587 2.719
Cole Hamels 104 21.10% -0.134 0.679 0.545 2.582
Kyle Freeland 307 35.05% -0.889 1.750 0.861 2.458
Jordan Montgomery 154 18.78% 1.031 -0.571 0.460 2.452
Wade Miley 360 36.92% 0.071 0.768 0.839 2.273
Alec Asher 80 32.26% 0.672 0.054 0.726 2.251
Trevor Cahill 260 38.35% 0.605 0.232 0.837 2.183
Zack Godley 167 38.39% -1.370 2.196 0.826 2.151
Casey Lawrence 87 45.31% -0.151 1.125 0.974 2.149
Martin Perez 359 37.28% 0.508 0.232 0.741 1.987
Tim Adleman 127 22.24% -0.545 0.947 0.402 1.805
Robert Gsellman 427 51.57% 0.070 0.857 0.927 1.797
Johnny Cueto 206 18.51% 1.021 -0.749 0.272 1.467
Kendall Graveman 549 74.69% 0.672 0.322 0.994 1.331
Clayton Richard 512 56.83% -0.214 0.947 0.733 1.290
Luis Perdomo 407 59.50% -0.462 1.214 0.752 1.264
Dylan Covey 157 27.30% 0.624 -0.303 0.321 1.175
Jhoulys Chacin 321 38.44% -1.175 1.571 0.396 1.031
Kyle Hendricks 368 45.43% 0.056 0.322 0.378 0.831
Tanner Roark 453 39.84% 0.299 -0.035 0.264 0.662
Jake Arrieta 440 52.57% 0.883 -0.571 0.312 0.593
Chad Kuhl 492 64.48% 1.171 -0.839 0.332 0.516
Jacob Turner 101 58.72% -0.737 1.036 0.299 0.509
Kyle Gibson 204 33.55% -1.286 1.393 0.107 0.319
Francisco Liriano 239 42.60% 0.434 -0.303 0.131 0.307
Jesse Hahn 439 61.74% -0.084 0.232 0.148 0.240
Edinson Volquez 392 48.88% 0.209 -0.125 0.085 0.174
Noah Syndergaard 175 41.77% -0.460 0.500 0.040 0.095
Jeff Samardzija 348 33.79% 0.320 -0.303 0.017 0.050
Jerad Eickhoff 165 17.82% -0.048 0.054 0.006 0.035
SOURCE: PITCHf/x





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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Jeagle
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Jeagle

Interesting analysis. What i found really crazy from the extended list was Paxton is listed at 10th with 62% usuage and Walker listed at 14th for the list throwing it 56% of the time.