Hiding From The Regression Monster

Look, no one wants to be the well actually guy when it comes to baseball players putting up numbers beyond their career norms. What happens on the field is what happens on the field — who cares that, well, maybe it won’t happen next time? But nevertheless, it is important to try to figure out who is due for regression in order to set our expectations as fans and properly assess what our lying eyes are seeing. And moreover, while we tend to use the term “regression” negatively, as in “who is about to come crashing down to Earth,” we can also use it positively, as in “who is due to start playing better?”

So let’s take a look at a few Red Sox hitters and figure out how much of their performance is for real.

Reese McGuire

Reese McGuire is a 28-year-old catcher who, prior to being acquired by the Red Sox at the trade deadline last year, had never been an asset with the bat, with just 9 career homers and an OBP that hovered around .300. Then he put on a Red Sox uniform and, inexplicably, hit 3 home runs in the last two months of the 2022 season to go along with a .337 batting average and .377 OBP. And so far this season, he’s followed that up with a .345/.379. So did he figure something out, or is he getting lucky?

Well, it’s tempting to say he’s figured something out, given that the increased production has now carried over from one season to the next over the course of 168 at-bats. But the reality is that his .345 batting average this year has been fueled by soft contact that’s found holes. He has just 4 extra base hits all season (none of which are homers), his average exit velocity is below league average, and his expected batting average is just .231, which pretty much lines up with his career mark of .245. In other words: his batted ball profile just doesn’t support the results so far. Expect a big slump that will bring his numbers back down soon.

But hey, he’s not necessarily the primary catching option anymore, is he? So let’s take a look at the other dude behind the plate.

Connor Wong

Your eyes aren’t deceiving you with Connor Wong. He is hitting the ball hard, with an average exit velocity over 90 MPH, which puts him in the 74th percentile. That’s given him 3 homers on the year, to go with a tidy .257/.313/.459 slash line, numbers that are easily above average for a catcher. So in light of the fact that, unlike Reese McGuire, he’s actually hitting the ball hard, he must be for real, right?

Well, not so fast. Connor Wong hits the ball harder than the average big leaguer. And yet, he also makes weak contact more frequently than the average big leaguer (7.5%, compared to the league average of 3.8%.) How do you square this? The answer lies in the fact that Wong is very much a free swinger. In fact, he swings at exactly 1 out of every 3 balls he sees (balls as in pitches outside of the strike zone, not literal balls.) So while he may hammer pitches in the zone, his approach leads to a lot of swing-and-miss and weak contact against pitches outside the zone, along with few walks.

What we may have here is a case of big league pitchers challenging an unproven rookie. As the proverbial book on him begins to circulate, look for them to stay away from the plate a bit more, forcing Wong to adjust.

Now let’s take a look at another player struggling with plate discipline.

Rafael Devers

Wait, Raffy Devers is struggling?!?! He leads the American League in both homers and RBI, how could he be struggling!

Well, despite the power, Devers is underproducing in pretty much every statistical category across the board. His OBP sits at a paltry .301, 44 points lower than his career average. His slugging is down, his batting average is down, his walks are down, and his strike outs are up. What’s going on here?

The fact is that Devers is a guy who has struggled to consistently control the strike zone throughout his career. He goes through extended stretches where he swings at almost everything he sees, then he settles down and starts laying off balls for weeks at a time, then he loses it again and the cycle repeats.

Take a look at how often Devers swings at pitches outside of the zone compared to a more disciplined hitter in Justin Turner:

Obviously Tuner chases pitches much less frequently than Devers in general. But what those charts further show is that Turner is much better at maintaining a consistent approach, whereas Devers tends to swing wildly from one approach to another. So far in 2023 it’s been a wild ride already:

It’s likely that his inability to maintain his approach has led to his walk rate plummeting to 5.9% this year from 8.1% last year and 9.3% in 2021. But I have every reason to believe that, just as he has in the past, he’ll once again rein in the free-swinging for an extended stretch in the near future. And in light of the fact that, even as he’s struggled to do so early on this year he’s still been hammering the ball, I’ll make another prediction: when it’s all said and done, 2023 will be the best year of Rafael Devers’ career.

Now let’s move on to someone else who seems certain to have the best year of his career.

Alex Verdugo

After finishing 2022 with an fWAR of just 1.2, Verdugo is already at 1.3 in 2023. . . and it isn’t even Mother’s Day. And while, on the offensive side of things, some of that is coming from improved contact and on-base skills (his batting average sits at .307 compared to his career mark of .288, while his OBP is at .379 compared to .344) the most drastic improvement is coming in the power department.

Verdugo slugged just .405 last year and has never hit more than 13 homers for an entire season. But he’s slugging .504 with 5 bombs already in 2023. Is it luck or something more? The answer looks like it’s a combination of both.

For one thing, Verdugo was fairly unlucky in 2022. Based on the quality of his batted balls, he should have had 3-5 more home runs last year, and that .405 slug should have been around .430, which is more or less his career mark. He also got nailed by the shift. Verdugo was shifted about 24% of the time in 2022, with his wOBA dropping to .280 in those situations compared to .336 without the shift.

But there’s no question that he’s also getting a little lucky in 2023. His slugging percentage should probably be closer to .460 based on batted ball quality. And he’s not actually hitting the ball all that hard: he’s bang near league-average in exit velocity, hard-hit percentage, and barrel percentage. In fact, his batted ball profile actually looks fairly similar to last year’s thus far:

That isn’t to say the none of the improvement is real. The increase in walks and xwOBA appears to be a direct result of the fact that he’s chasing pitches outside the zone, swinging-and-missing, and swinging in general less than he ever has in career. He went from swinging at the first pitch over 21% of the time in 2022, to just 12% this year. And when he does swing at a pitch inside the zone, he makes contact over 95% of the time, a career-best mark. And further, the sprint speed and arm strength numbers indicate that he’s both healthier and in better shape this year.

Alex Verdugo is a better baseball player, but he isn’t this good. He’s going to come back down to Earth, and he’s not going finish in the top 5 of the AL MVP voting like he would if the season ended today. But thanks to improved athleticism, defense, and his approach at the plate, he’s still due for a career year.