Breaking Down Liam Hendriks’ Home Run Problem

Eloy Jiménez’s torn pectoral muscle; Luis Robert’s torn hip flexor; Nick Madrigal’s torn hamstring; Yasmani Grandal’s numerous ailments; Zack Collins’s flagrant inability to catch; Yermín Mercedes, Billy Hamilton, and Brian Goodwin salvaging the depth chart in spite of the Adam Eaton experiment; subsequent trades for César Hernández, Ryan Tepera, and Craig Kimbrel; Andrew Vaughn playing left field; Andrew Vaughn playing right field; Andrew Vaughn playing second base — these are a smattering of the dramas that have encompassed the 2021 Chicago White Sox.

They’re among the many reasons there hasn’t been much of an extended discussion (until lately) about Liam Hendriks, who leads the American League with six blown saves, has blown three of his last six save opportunities, and has a 5.68 ERA since July 1. He’s been worth 1.2 fWAR in 50 innings this year after accumulating 5.2 in his previous 110, providing roughly half of his former value on a per-inning basis.

Let’s not start out on too critical of a note, though. There are other reasons Hendriks’ periodic struggles haven’t been a significant concern until his recent spate of lost leads. He does lead the AL in blown saves, but he also leads the league with 26 converted saves, and went a full 19 appearances without allowing a run between April and June. He closed out the All-Star Game in hilarious, mic’d up fashion. By FanGraphs’ leverage stats, there are few pitchers in the game who have consistently worked more in tight, high-pressure scenarios. Furthermore, his overall stats aren’t even that bad — a 3.42 ERA is far from awful. It’s just not the 1.80 mark the team paid for after 2019 and 2020. Finally, Hendriks’ strikeout-to-walk ratio remains pristine; with just six walks against 82 strikeouts, he’s lapping the MLB field by more than two points with a 39% K-BB.

By both statistics and the mouths of the fanbase, it’s clear that home runs are the problem. Hendriks leads all MLB relievers with 11 home runs allowed, nearly twice as many as he allowed in 2019 and 2020 combined and already the most he’s ever conceded in a season since he converted full-time to relief in 2015. It’s the homers in particular that have tanked his typical late-inning consistency — all six of those blown saves have been the product of ill-timed home runs, several of them with two outs — and it’s their seemingly freak nature that makes them hard to figure out. Looking at his full suite of stats from the last few years, it looks as if the spate of home runs can’t be chalked up to Hendriks simply getting worse as a pitcher. In fact, by some measures, he’s better than he’s ever been.

Baseball-Reference, FanGraphs

Like I mentioned before, the strikeout and walk numbers are actually better than ever, and anybody who’s watched him pitch this year knows his pure stuff has been as good as advertised (more on that in a moment).

The three columns I’ve highlighted tell two different stories. They’re somewhat contradictory, but they give us a hint at where to look next. First, there’s his xERA, which is basically just Statcast’s way of converting its walk, strikeout, and quality-of-contact measurements like wOBA and xwOBA to an ERA scale. The takeaway here, then, is that according to Statcast, Hendriks hasn’t actually been any worse this year than in the past, which certainly jibes with his walk and strikeout numbers.

Then there’s the second highlighted column, a homers-per-fly-ball rate that’s literally four times higher than it’s been in the past. League average is about 13%, and HR/FB is a notoriously inconsistent stat. It’s highly doubtful that one out of every five fly balls Hendriks allows will leave the yard going forward. All of this tracks well with the feeling that many of these blown saves are simply freak incidents that probably shouldn’t have any bearing on his future usage.

That’s certainly the thought train I’m leaning towards right now, but let’s hear both sides — there is that third highlighted column, and the one to the left of it. Hendriks is giving up a fair amount more hard contact than he did last year, and most importantly, it’s hard contact that’s hit in the right launch angles. HR/FB might have a lot of random variation from year to year, but you rarely see a pitcher’s barrel rate triple without something else going on under the hood.

Therein lies another part of the problem. When you go look under the hood, it’s still hard to find anything actually wrong. Hendriks is throwing his fastball quite a bit harder than he was in 2019 and 2020; its movement profile hasn’t changed much; he’s not throwing it in the zone any more or less, and he’s doing just as well in terms of drawing strikes, swinging or otherwise.

Pitch Leaderboard, Baseball Savant

That’s a mouthful of numbers right there (and please feel free to leave questions in the comments or on Twitter if you don’t know what some of these mean or want to learn more!), and none of them particularly explains why Hendriks is suddenly giving up homers at such a high rate. Just that there’s something off with the kind of contact he’s allowing on the fastball. We’ll get there in a moment.

It’s the same story with his slider and curveball, the former of which has actually been considerably better this year across the board than in 2020. Again, they aren’t behaving super-differently, and they’re not any less effective by most important measures.

Pitch Leaderboard, Baseball Savant

Pitch Leaderboard, Baseball Savant

At the very least, this confirms that the fastball is the main problem. Now that we’ve identified that, the next place to look is location. Is Hendriks throwing the pitch in worse spots than he was in Oakland? Here’s a back-and-forth of where Hendriks threw his fastballs in 2019-20 (it was more or less the same), and where they’ve been going in 2021.

I don’t really see much there, honestly. If anything, his locations have been a bit better on the whole, which makes the picture even more confusing. Hendriks is throwing it harder, and he’s throwing it more in spots where it should (in theory) be harder to hit. Looking purely at the numbers and visuals, the conclusion one ought to come to is that bad luck really is the most reasonable explanation for Hendriks’ struggles.

That’s partially true. But one should never look solely at the numbers and visuals, of course. Watching the games is pretty important, too! A combination of all those numbers that I laid out above with watching a lot of Hendriks tape (home runs and otherwise) leads me to a slightly more nuanced conclusion.

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Game tape breakdown

It’s undeniable that Hendriks has had more than his fair share of undeserved misfortune. That 20% HR/FB will come down, almost without question. That doesn’t mean he’s been perfect. In spite of the dearth of walks, Hendriks’ command isn’t elite — he misses down the middle of the plate a little more than one might be comfortable with. But there’s not much evidence that he’s missing down the middle any more than in the past. The opposite, in fact. To my eye, the biggest difference is that lately, hitters have simply been ready to hit those mistakes much more than in the past.

What does that mean, in practice? The ninth-inning meltdown that preceded Tim Anderson’s already-legendary walk-off in the corn is an excellent demonstration of how hitters can adjust to elite pitchers in spite of their most electric stuff.

First, we have to know the basic scouting report on Hendriks. He throws mostly fastballs, backed up by that nasty slider and, roughly one time out 10, a diving, change-of-pace curveball that does a pretty good job mirroring his slider.

Hitters have known for a while now that they’re going to get a lot of fastballs. It hasn’t stopped Hendriks before. Another thing they probably know is that even more so now than in years previous, they’re almost guaranteed to get a fastball on the first pitch of the at-bat.

Do you think that’s something the notoriously light-hitting Tyler Wade might have been thinking about when he managed to get enough barrel on a mid-zone first-pitch fastball to take it into the outfield for a hit?

OK, well, that’s just one hit. If you remember correctly, Hendriks then proceeded to strike out both D.J. LeMahieu and Brett Gardner with the same heat that Wade flipped into the outfield.

Great, that’s what Liam does best. The thing about relief pitching, though, is that the sample sizes are small, and the margins are thin. If hitters are just 5% more adjusted to Hendriks than they were last year, it only takes a few good swings to make it look like a lot more than 5% on the overall stat sheet. Now he has to face Aaron Judge, who some might refer to as a “pretty good” hitter. Remember how I said Liam doesn’t have great command? His filthy stuff lets him get away with it more often than most. But to Aaron Judge, this sequence of locations was probably destined for disaster.

Even at 99 mph, you’re just not going to get Aaron Judge to miss on that pitch down the middle twice. It’s a consistent theme among the home runs Hendriks has allowed this year. Again, it doesn’t necessarily seem like he’s throwing any more fat pitches than he did previously. Hendriks is just getting punished for them more, and at the worst possible time.

Judge isn’t the only one who’s taken advantage of it. When Baltimore put up two in the ninth against Hendriks to tie the game on July 11, it wasn’t because of a crazy rally or any magnificent displays of hitting. It was because Hendriks threw Trey Mancini a fat fastball that he was clearly ready for, even at 98 mph.

It was the same story against Daz Cameron a month earlier. Maybe Hendriks gets away with this pitch when a hitter is thinking about the slider, but is there any doubt here that Cameron was looking for a first-pitch fastball — and prepared to hammer it if it was over the middle?

One more, for good measure. Nothing illustrates the importance of preparedness like this one. In a vacuum, this is actually a pretty good pitch. But if a hitter is ready and looking for it, it doesn’t matter. This home run would be pretty impossible if Willie Calhoun wasn’t looking for that exact pitch in that exact spot.

Anyhow, back to the Field of Dreams. After the Judge home run, Hendriks still had a one-run lead and two outs in the inning. Once again, though, the lack of command came to bite him. Hendriks walked Joey Gallo on five pitches, with all three of the fastballs he threw not coming particularly close to the zone.

So as Giancarlo Stanton comes up to hit as the go-ahead run, he knows a few things. He’s just watched three fastballs to Gallo that were easy takes, immediately after Judge had begun his at-bat with two of them. He sees that Hendriks doesn’t have a handle on his fastball, and he also knows that Hendriks typically throws almost nothing but fastballs on the first pitch. Presumably, he also knows that while his slider is a good pitch, it’s not a get-me-over; it barely lands in the zone a third of the time.

All that being the case, Stanton probably didn’t have to think too hard about his approach. There’s no reason to try to compete with that amped-up heater as long as he has no idea where it’s going. Knowing the slider probably isn’t going to be a strike either, the strategy is pretty simple: if Hendriks hangs a slider over the plate, go get it. If it’s low, let it go, and if it’s a fastball, let him prove he can throw it for a strike first.

On average, hitters around the league swing at the first pitch roughly 30% of the time. Stanton, meanwhile, offers at the first pitch just 18% of the time. Last year, it was 15%. He’s a patient hitter, and does not swing at the first pitch unless he’s looking for something and is almost certain he’s getting it.

So do we think Stanton got was he was looking for on this first pitch here?

Again, Hendriks throws a first-pitch fastball roughly nine times out of 10. The fact that Stanton was able to read him well enough to look out for that pitch and execute the right kind of swing on it doesn’t bode well for the overall approach. When Hendriks’ command is off, like most pitchers, he becomes more predictable. Perhaps two years of dominance has caused hitters to do a little more homework than in the past.

It doesn’t help that he hung the bejesus out of that ball. That, too, is an unfortunate pattern. From a fan’s perspective, it’s really hard to attribute all those blown saves to “luck” when they’re coming on pitches like this.

Or this.

What do both of those have in common? They’re sliders right down the middle on a 1-2 count. Relatedly, what’s the only count in which Hendriks throws the slider more often than the fastball? Hazard a guess: It’s 1-2. Just like with the fastball, Hendriks isn’t hanging the slider any more or less than usual. But this season, at least a couple more hitters have been a lot more ready for it when he has.

That is where the nuance lies between Hendriks’ seemingly-fine peripheral numbers and underlying stuff, and the reality of his performance. If Hendriks throws 1,000 pitches in a season, a hitter needs better recognition or anticipation on just a handful of them to swing the balance of a season. Such is the life of a relief pitcher.

So, 2,000 words later, it’s fair to say that Hendriks hasn’t changed much. He is what the White Sox paid for, and ultimately, he’s still probably worth it. At the same time, his margin for error is thinner. Hitters are just a little more prepared to hit Hendriks’ mistakes. Relatedly, perhaps they’re also better equipped to take advantage of the occasions that his command is off. Combine that with some bad batted-ball luck, and you’ve got a pretty solid explanation for all those new barrels. All it takes is an extra five or six good swings in those situations to turn a 1.80 ERA into a 3.30 ERA.

The good news is that it’s clearly fixable, because there’s not much “wrong.” If Hendriks is the same as a pitcher, he can always adjust his approach. He can fine-tune his control, if not his command, and his entire arsenal is good enough that he can certainly tweak his pitch mix without suffering for it.

All in all, it’s frustrating, but it’s no reason to panic: Hendriks is still one of the best relief pitchers in the game. He’s no stranger to adversity, and it feels more likely than not that he’ll make the necessary adjustments. If he’s still blowing saves on a weekly basis next month, there will be plenty of cause for concern. I suspect that won’t be the case.