Kopech Turns to Rubble

Kim Klement-USA TODAY Sports

The Chicago White Sox really ought to be praying to whatever deity is currently tormenting them with plagues of locusts and pestilence, and thanking her that even more conspicuous travesties against baseball are occurring in St. Louis and Oakland.

A couple weeks ago, Jay Jaffe wrote about the terrible goings-on over in Chicago in general terms. I would’ve titled that piece “And I Looked, and Behold a Pale Hose: and His Name that Sat on Him Was Death, and Hell Followed With Him.” Jay opted for the more direct “The White Sox Are Utterly Terrible,” which they were then and are now.

Their failures this season have been so complete that it’d be unfair to blame any one player or coach, and at any rate that’s not the purpose of this post. That purpose: to examine a player once viewed as a unique talent, for whom things have gone badly off the rails. Michael Kopech is in the rotation full-time — a rarity in his Bright Eyes concept album of a career — but things are not going well.

Actually, “not going well” is a charitable way to put it:

Michael Kopech, Quel Dommage
ERA FIP xERA K-BB% WAR
Value 5.74 7.31 7.61 6.80% -0.6
Rank* 72nd 75th 75th 72nd 75th
*Out of 75 qualified pitchers, through 5/14

Looking at where Kopech ranks in certain key categories, you’d have to do a lot of work to prove that he hasn’t been the worst starting pitcher in baseball so far this year. “Now hang on a minute,” I can hear you thinking, “isn’t the actual last-place starter in ERA your man Lance Lynn?” To which I can only respond: 1) Yes. 2) Lynn’s FIP and xERA are only in the 5.00s. And 3) I’m not emotionally ready to contemplate the idea that Lynn might be cooked. Maybe someday, but not today. So today we’re talking about Kopech.

Kopech, for those of you who don’t remember, used to be one of the hardest-throwing pitching prospects of all time. He came to Chicago in the Chris Sale trade as the JC Chasez to Yoán Moncada’s Justin Timberlake. If you want to feel old, that trade happened in 2016. It was during the Obama administration. They’ve released 18 Marvel movies since Kopech got traded.

It took Kopech a minute to get to the majors after the trade, then he missed the end of 2018 and 2019 while recovering from Tommy John surgery, and opted out of the 2020 season. He’s been mostly healthy since then, but he’s still missed a month here with a hamstring strain and a month there with shoulder inflammation. A generation ago that might have been enough to warrant a move the bullpen all on its own, but nowadays the 25 starts Kopech made in 2022 are basically par for the course. With that said, Kopech is now 27 years old and nearly five years removed from his major league debut, but he’s thrown just 245 1/3 innings in the big leagues.

It wasn’t always a given that he’d make it in the rotation. (Though Kopech is currently “in the rotation” in such a way that recalls the thruster malfunction on Gemini VIII that sent the spacecraft into an uncontrollable spin and nearly killed Neil Armstrong.) In 2021, Kopech was highly effective as a reliever — sometimes a multi-inning guy in the days when that was in vogue. There was talk that he and Garrett Crochet could combine to give the White Sox the hardest-throwing bullpen ever. Crochet is nearing his own return from Tommy John surgery, by the way; considering that his last major league action came in the 2021 playoffs, he must be living the Troy Barnes pizza GIF right now.

Back to Kopech, though. The thing that made him such a remarkable prospect was his fastball velocity. He’s still throwing hard, but not so hard as to be conspicuous, or to make up for numerous other shortcomings.

Over parts of his four seasons in the majors, Kopech has thrown 21 pitches at 100 mph or harder, of which just one has come in the past two seasons. Now, only 19 starting pitchers have hit triple digits even once in that span, so it’s still impressive. But Spencer Strider has done it 46 times. Hunter Greene’s done it 418 times. Here’s a fun comparison: Since the start of 2022, Kopech has thrown 40 pitches at 98 mph or harder. Greene has thrown 40 or more pitches at that velocity in exactly half his career starts.

Kopech’s Pitches at Certain Velocities
Velocity Number of Pitches Rank
100+ 1 T-15th
99+ 7 23rd
98+ 40 22nd
97+ 198 21st
SOURCE: Baseball Savant
2022-Present

So when an 80-grade fastball, or at least a 70, turns out to be merely plus velocity-wise, what happens to the rest of the repertoire?

Most of the pitches Kopech throws are either fastballs or sliders. He’s getting less movement on his changeup and curve than he did last year, but he’s only thrown a few dozen of each this season and has barely thrown his changeup since returning from Tommy John.

Maybe he should start. The fastball, all things considered, is fine. Not that “fine” is the word you’d want to use to describe a pitcher who once had his fastball as his calling card, but his whiff rate and contact numbers on the heater are middle-of-the-pack.

The problem is he’s really only using one secondary pitch, the slider, and it’s getting wrecked:

Kopech’s Slider in 2023
Whiff% HardHit% xwOBA
Value 21.5 59.1 0.417
Rank 106th 113th 112th
SOURCE: Baseball Savant
Minimum 100 sliders thrown this season (115 pitchers)

At least, that’s one of his problems. Kopech has never really gotten the kind of swing-and-miss you’d hope for from a pitcher with his arm strength, at least out of the rotation. Some pitchers get around that with impeccable command and control, but unfortunately for Kopech that’s eluded him as well.

Last season, among 140 pitchers with at least 100 innings pitched, Kopech was 117th in K-BB%. Or more to the point, he had the second-highest walk rate among that cohort. As you’d expect, he was in the bottom 30 in FIP as well, at 4.50. And while that’s not very good, it’s better than you’d think from a pitcher who walked so many batters without posting a particularly high strikeout rate.

That’s because Kopech did a decent job of keeping the ball in the yard last year. A 1.13 HR/9 rate from a fly ball pitcher isn’t terrible, and his HR/FB rate of 9.4% was better than league average.

Which brings us to problem no. 3. He’s still walking a ton of batters — 14.6% of opponents, which is the highest among qualified starters by almost a full percentage point — but he’s not keeping the ball in the yard anymore.

Kopech’s HR/FB ratio is now up to 20.7%, third-highest among qualified starters. (Lynn is no. 2 on the list, so maybe this is all about the White Sox switching out their baseballs for racquetballs or something.) That’s bad enough out of context — 12 dingers off 58 fly balls. But few pitchers have a heavier fly ball bias than Kopech; he’s has the fifth-highest FB% among starting pitchers, and the fifth-lowest GB/FB ratio. So when one in five fly balls leaves the yard, it’s a problem.

This is one of the few areas in which things could have been a lot worse for Kopech. You’d think that the pitcher with the highest walk rate in baseball would have a lot of men on base when the ball goes out. On the contrary: Of the 12 home runs he’s allowed, 11 have been solo shots. The other came with just one runner on base.

For contrast, 57.9% of home runs league-wide this year have been solo home runs, and the average home run has plated 1.59 runs. The difference between that and Kopech’s 1.08 comes to about six extra runs; in other words, if Kopech had allowed the league-average number of runs per homer, his ERA would be north of 7.00 right now.

It’s not what you want, as one World Series-winning manager would say.

When a player is struggling as badly as Kopech is, I try to look for positives, to search for a light at the end of the tunnel. He’s healthy at the moment, which has not been a given for this pitcher, and that’s no small matter. But apart from that, well, the biggest reason to be optimistic about Kopech is that things can only get better from here. For whatever that’s worth.





Michael is a writer at FanGraphs. Previously, he was a staff writer at The Ringer and D1Baseball, and his work has appeared at Grantland, Baseball Prospectus, The Atlantic, ESPN.com, and various ill-remembered Phillies blogs. Follow him on Twitter, if you must, @MichaelBaumann.

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raregokusmember
9 months ago

We need a weekly post with Baumann’s alternate headlines for every piece. Truly inspired.

soddingjunkmail
9 months ago
Reply to  raregokus

bring back notgraphs