2023 SABR Analytics Conference Research Awards: Voting Open Now!

Yesterday, Greg Wellemeyer gave you the lay of the land about strikeouts in the majors, and the punchline for those of you who may have been trapped under something in a dark room for the last several years is that strikeouts have gone way, way up over the past decade.

I’m not going to spend time on the guys who broke out into the top tiers of bulk strikeout accumulation simply by virtue of pitching more big-league innings this year (unless that leap came out of nowhere). And on the flip side, I won’t talk about the guys who “disappointed” simply because they missed time with injuries. Especially with pitchers, that’s not a particularly notable development in most cases. Instead I’m going to focus here on the players who demonstrated a skill change, for better or worse, in striking guys out and see if we can figure out what happened to drive the change in their performance.

Overachievers (yes, and proud we are of all of them)

Clayton Kershaw, LHP, Dodgers

2015: 301 total strikeouts (1st), 11.64 strikeouts-per-nine (2nd)
2014: 239 (7th), 10.85 (2nd)

There isn’t much to say about Kershaw that hasn’t been said already, but it’s certainly worth taking a moment to appreciate the first 300-strikeout season in over a decade. This was the year it all came together in terms of both stuff and durability, as he improved on last year’s leaps forward in overall whiff rate while making every start. He didn’t induce more fishing expeditions out of the zone, nor did he benefit from Yasmani Grandal passing out free strikes like Halloween candy all season. He just straight-up beat more hitters with more pitches than he ever has. He boasted three offerings that were top-16 among starters in their respective classifications at generating whiffs when batters offered, and he went to his slider and curve—both pitches that drew cold, dead air from more than two out of every five swings—more than ever. The slider in particular has evolved over the past two years into a harder, tighter pitch, and its whiff rate has in turn jumped up with the velocity. It’s scary to think that a pitcher as good as Kershaw can still learn and improve, but that’s what he’s done, and in 2015 he was the rare example of a first-round pick who manages to dramatically out-produce even the most aggressive of preseason projections.

Chris Archer, RHP, Rays

2015: 252 (4th), 10.70 (5th)
2014: 173 (T-32nd), 8.00 (T-48th)

Archer’s another pitcher who added some extra oomph to his slider in 2015. He threw the pitch about 1.5 mph faster while maintaining constant horizontal break, and he threw it significantly more often, an increase of about 11 percentage points in the share of his overall mix. Given the well-above-average whiff rate the pitch boasts, that alone would be enough to drive a massive jump in strikeout numbers, but he also dramatically improved the performance of his changeup against left-handed hitters. He traded in some drop for much greater fade on the pitch, turning it into a legitimate put-away offering to tame southpaws. He added over seven percentage points to his whiff rate against lefties, and the change’s development was a big reason why.

Dallas Keuchel, LHP, Astros

2015: 216 (9th), 8.38 (37th)
2014: 146 (T-57th), 6.57 (106th)

I should just haphazardly draw a heart around Keuchel’s name and call it a day, but any chance to spill some internet ink about the depths of my love for this guy is a chance I’ll take. Yes, he cracked the top 10 in bulk strikeout volume in no small part thanks to tossing so many innings this year. But as you’ll note from the rate numbers, he took a massive step forward in maximizing his strikeout returns on a per-inning basis as well. And his improvement here was almost entirely a splits thing, as his whiff rate remained relatively constant against lefties. Opposite-handed hitters, on the contrary, fared much worse in the contact department against Keuchel this year. He added over five percentage points to the whiff rate of both his slider and change against righties, and he worked much more often off a two-seamer to set them up.

The swing-and-miss rate alone doesn’t fully explain the size of the bump in Keuchel’s strikeout rate, however, and when you dig deeper, he didn’t generate a greater rate of called strikes, nor did he throw more of them in general than he did in 2014. He threw slightly less, in fact. Without getting Jacque Cousteau deep into his pitch selection and the like, there sure seems to be some anecdotal evidence in these numbers that Keuchel just got better at sequencing his pitches and executing in context. He became more efficient, in other words, in his timing of a similar number of strike outcomes. And that’s fascinating and impressive.

James Shields, RHP, Padres

2015: 216 (11th), 9.61 (14th)
2014: 180 (26th), 7.14 (82nd)

James Shields. Jaaaaames Shiiiiieeelds. Ol’ “Big Game” Jayyyy can’t do this. The strikeouts were nice and all this year, but as a recovering Shields owner in multiple leagues I can tell you they were cold comfort for an otherwise spectacularly inconsistent season. Despite racking up the fifth-most Ks in the National League, he barely staggered his way into the top 40 for NL-only value. Most of Shields’ new strikeout skill derived from a new curveball, which took a much deeper shape and induced the 13th-best rate of whiffs-per-swing on the year. He threw the pitch more often, and he also utilized his cutter much more selectively against righties to help boost that pitch’s strike-generating performance. Of course, ultimately how many swings-and-misses he generated doesn’t matter nearly as much when the contact that does get produced from time to time is as loud as the contact Shields gave up in 2015. Draft pedigree and issues of return on investment aside, the whiffs kept Shields fantasy-relevant in shallower leagues even though the bulk performance was well below expectation, and that’s an increasingly important theme for the back end of your fantasy rotation. The environment is such that finding guys who can still miss bats despite underwhelming contributions in the rate categories is important as you look to fill out innings.

Raisel Iglesias, RHP, Reds

2015: 102 (101st), 9.94 (8th)
2014: N/A

Here’s my first cheat of the exercise, but Iglesias earned it as possibly the best return of FAAB dollars of any pitcher in the second half. This wasn’t a case like a de Grom, or a Carrasco, or a Cole, where we knew that the performance indicators were there if they could just log enough innings. No, nobody really knew what the Reds had with Iglesias, and until the beginning of August, the Reds really didn’t know either. Or maybe they did. What’s most interesting about Iglesias’ profile is the lack of real swing-and-miss development over the course of the season. He threw more sliders and less four-seamers as the season wore on, and that’s a good thing because his slider generates a solidly above-average whiff rate. He also showed himself extremely adept at stealing first strikes with the pitch, and by August he was throwing the pitch to open more than a third of at-bats. The “pitching backward” strategy at the heart of his success poses some uncertainty about his ability to continue producing as scouting reports adjust off a winter of study. But for a “probable reliever” who came out of left field, the underlying strikeout skillset you want to see is there.


Felix Hernandez, RHP, Mariners

2015: 191 (20th), 8.52 (35th)
2014: 248 (4th), 9.46 (12th)

The King was cruising along for the most part out of the gate, with a whiff rate only marginally below last year’s frequency through the end of May. But then he suffered a velocity dip in June, during which time his whiff rate with both the changeup and slider cratered, and whether he attempted to adapt on is attack on the fly to diminished stuff or what, he never got fully back on track in the whiff—or really any—department. 191 strikeouts is obviously nothing to sneeze at, but it was the first time he failed to crack 200 whiffs since 2008, and the nearly 60 fewer strikeouts he racked up relative to 2014 were a big deal to lose from your SP1. His changeup was far and away the largest culprit, as it backed up considerably from an elite swinging-strike rate to merely an average one overall (and a significantly below-average number against left-handed hitters). Add in that he went to the pitch more often overall against the fairer-handed, and you’ve got your decline in box once the step back in innings from last year to this is factored in. Felix’s ADP in the spring will be one of the more interesting to watch, as he had successfully defied most all convention in churning out 200-inning seasons and fighting off the typical performance decline that usually mirrors velocity decline. Still, the regression of his performance with the secondaries should serve to deflate his price tag; the question will be how much.

Johnny Cueto, RHP, Royals

2015: 176 (25th), 7.47 (72nd)
2014: 242 (5th), 8.94 (27th)

Cueto’s overall performance slide corresponded with a drop in strikeouts and a sharp increase in the quantity of solid contact he yielded, and that’s never a fun combination to ponder if you’re rostering the responsible pitcher. He worked off his four-seamer more than he ever has before, and while that pitch generates an above-average number of whiffs hitters seemed to have more luck picking off his slider, cutter, and change as a result. The numbers don’t quite do enough to explain away the whiff gap, however. Cueto is one of the tougher pitchers around to analyze mechanically on account of his frequently migrating release point, but one thing that sticks out in his arsenal is marginally less vertical movement across the board, and that change corresponds with a higher overall release point on all of his pitches. So in other words, while his chase and contact rates overall appear constant relative to years prior, it’s possible hitters were picking up the ball that much better against him this year. He struggled putting guys away relative to his career norms, as both his slider and change in particular got hit harder with two strikes.

The good news is that there’s nothing substantively alarming in the data like you may perhaps expect when seeing so significant a drop-off in whiffs: he didn’t lose a couple ticks off his fastball, nor did he forget how to throw his cutter. And for a pitcher with as much experience as Cueto in shifting his mechanics and finding repeatability in different forms, that may just portend a reasonable expectation for rebound in 2016.

Jeff Samardzija, RHP, White Sox

2015: 163 (42nd), 6.86 (90th)
2014: 202 (13th), 8.28 (36th)

You name it, and chances are Shark did it poorly in 2015. The cratered strikeout rate was just the icing on the cake of a disastrous campaign that saw him return as much AL-only value as the likes of Matt Albers. The biggest problems in the pile for Samardzija’s whiff rate lay with his slider and split, two pitches which just so happen to come out of his hand at virtually the same release speed. His release point on the splitter wandered a bit north of where he threw every other pitch, and while the amount of vertical “drop” on the pitch was consistent with prior efforts, the pitch location migrated an average of four inches closer to the bottom of the zone. That’s a big deal, as while batters offered at the pitch as often as they used to they made contact a staggering 17 percentage points more often. Add in a similar, though less-severe regression with his slider, and you’ve got more than enough of a disconnect to pinpoint his tumble to a below-average strikeout rate. Maybe he rebounds in the future, maybe he doesn’t. But the loss of both of his primary strikeout weapons is a huge cause for skepticism moving forward.

Jake Odorizzi, RHP, Rays

2015: 150 (T-54th), 7.97 (50th)
2014: 175 (T-30th), 9.32 (14th)

Odorizzi entered the year with plenty of reasonable expectation as someone capable of filling an SP3 slot in most leagues on account of his elite strikeout rate offsetting some of the contact issues that cropped up in his first full-ish season. Overall his seasonal value ended up looking awfully similar to his effort in 2014, though he got there in a different way: Instead of underperforming his FIP this year he overperformed to generate a solid ERA, he cut his walk rate (and with it his WHIP), and he offset a bunch of that gained value in lost strikeouts. There isn’t a ton of damning evidence as to why the whiffs dried up, however. He actually increased his whiff rate this year, largely by throwing a more effective splitter more often. He got hitters to two strikes significantly less often this year, however, working more often in the zone and allowing more early-count contact. That’s not a necessarily predictive development, however, insofar as the performance of his stuff took a small step forward overall. He’ll be an interesting name on draft day for 2016, one who’s decline in whiffs may scare some people off a bit but whose underlying performance suggests the true talent may be closer to the better-than-a-whiff-an-inning guy we saw in 2014.

Phil Hughes, RHP, Twins

2015: 94 (115th), 5.45 (130th)
2014: 186 (T-18th), 7.98 (52nd)

Everybody and their second cousin predicted some manner of regression for Hughes off his historic 2014, but I’m not sure even his most fervent detractors could’ve foreseen the utter and total destruction of his whiff rate this year. His arm angle wandered significantly farther south, leading to lost plane and angle on his pitches; his signature curveball hemorrhaged vertical drop and with it any semblance of bat-missing capability, as it backed up into a well-below-average swing-and-miss pitch. He lost a similarly catastrophic amount off his four-seam rate, as that pitch got absolutely destroyed by hitters far and wide to the tune of a .340 batting average-against and .605 slugging percentage-against. Ugly business, all around.

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