What Is Jackson Chourio’s Superpower?

I have a secret to tell, one that might surprise you. I think that baseball analysis is too complex. I can’t keep track of it all. There are too many numbers, too many ways to approach things, too many parts of the game that might be good in one context, bad in another, and neutral in a third. My whole job is to analyze baseball, and yet I find myself drowning in data more often than controlling it. My solution is to simplify. I look for players’ superpowers – carrying tools, in baseball parlance. Aaron Judge is power personified, with the rest of his game building off of that. José Ramírez is a bat control genius. Mookie Betts is the most coordinated man alive. Luis Arraez could hit soft line drives the other way in his sleep. These shortcuts help me think about how the rest of a player’s game fits in. But I have a problem: I’m trying to analyze Jackson Chourio, and I can’t figure out what his superpower is.

You might think it’s his speed. You wouldn’t be wrong, exactly. He’s one of the fastest players in baseball, and he uses that to his advantage all over the place. He’s an excellent baserunner and defender. He eats up ground in the outfield in huge loping strides, the kind of quick you only notice after the fact. I watch him and think he’s an above-average center fielder. The Brewers have only played him in the corners this year, since they’re overrun with excellent defensive outfielders and Chourio has the least experience, but he’s so good that if he ends up in a corner, he might be peak Jason Heyward there.

I guess we could stop the article there, but speed isn’t really a superpower for many great players. Sure, Bobby Witt Jr. and Elly De La Cruz are the current kings of sprint speed, but you don’t look at their games and say, “Oh, the main thing about them is that they’re fast.” That’s the territory of Billy Hamilton or Victor Scott II, and those guys just aren’t stars in the way that I think Chourio will be. I’m looking for an offensive weapon that makes everything work for him, one that explains how he’s hitting major league pitching at age 20.

Is it power? Chourio certainly has power. He hit 22 homers in Double-A at 19, and he’s tracking towards a 20-bomb season in the majors in his rookie year. But if you ignore the name and look at his statistics, we’re not exactly talking about overwhelming force here. The hardest ball he’s hit this year checks in below 110 mph. His 90th-percentile exit velocity, 104.1 mph, is almost dead average. His hard-hit rate is a bit better than that, but his barrel rate is a bit worse. If you were just glancing over the Baseball Savant percentile bars, you’d probably come to the conclusion that his power is average to below average. Strange!

I’d argue that this is a place where the seasonal averages don’t tell the full tale, though. In April and May, Chourio’s 90th-percentile exit velocity was lackluster – 103.5 mph, in the 38th percentile league wide. Since then, it’s surged to 106 mph, the 72nd percentile. His hard-hit rate is up from 42%, the 65th percentile, to 46.4%, the 83rd percentile. His groundball rate has declined from 52% to 48%, and it’s down to 45% since the start of July. That’s still higher than the league average of 43%, but it’s headed in the right direction. In other words, he’s both hitting the ball harder and getting it in the air more often. It won’t surprise you that his isolated power is trending higher and higher:

Still, I’m not ready to say that’s the answer. Being in the 72nd percentile for power is good, but it means 28% of major leaguers have been hitting the ball that hard or harder. Superman isn’t stronger than 72% of the world – he has super strength. Let’s keep digging to see if we can find something more satisfactory.

A quick interlude: One thing that surely isn’t Chourio’s superpower is pitch recognition. I’m partial to the swing/take charts you can find on Baseball Savant for explaining this. Here, for example, is a player who I’d say has exceptional pitch recognition:

Juan Soto knows what he’s doing up there. On pitches thrown to the heart of the plate, he swings at roughly an average rate. On worse pitches, he swings far less than average. You can’t fool him with chase pitches out of the zone, but he’s not too passive when you do come after him. Here’s another way that pitch recognition can manifest:

Corey Seager wants to swing, and so when pitchers throw him hittable pitches, he does just that. When pitchers avoid him, he’s able to rein himself in. I’m making no judgment as to whether Soto’s plan is better than Seager’s, or vice versa. They clearly have a similar skill, though. Chourio does not:

He swings as often as Soto when he sees pitches right down the pipe. He chases roughly three times as often. The comparison to Seager is even more jarring. The best place to be, all else equal, is swinging more often than average at crushable pitches and less often than average outside the zone. Chourio’s doing the opposite.

Even here, though, I have some good news. Again splitting the season roughly in half at June 1, Chourio’s aggression in the zone has improved; he’s swung at roughly 75% of heart-zone pitches since then, up from 68%. Meanwhile, his chase rate has ticked down slightly, from 32.7% to 31.5%.

Far more encouragingly, he’s been a lot better at identifying the edges of the zone. I define that in location terms; the area I’m looking at is just off the edge of the plate, in the shadow zone but outside of the rulebook strike zone. These are incredibly tough pitches to lay off, which is why they’re so effective. Batters swing at them 44% of the time, and when they do, the results are incredibly bad. In run value terms, pitches to the shadow-out zone that induce swings are worth 4.7 runs above average per 100 pitches for the pitcher. That’s the equivalent of a Clay Holmes slider, and more effective than any pitch thrown by a starter. On the other hand, taking those pitches is great; they’re balls, after all. Take a pitch just off the plate, and you transform the pitch from a Holmes slider to a Ross Stripling slider (-3.5 runs/100 pitches).

Chourio was getting absolutely eaten alive by these pitches early in the season. He swung at 55% of them over the first two months. He’s seen 126 of them since June 1 and swung at just 51, a 40.5% rate. That change has come with fewer swings at pitches on the edges of the plate, but eh, that sounds like a good change to make anyway, and we already know he’s swinging more often at pitches down the middle.

Put another way, Chourio was in the bottom 10% of all hitters when it came to bad swings in his first few months of major league action. Now he’s in the top 35%. He did it without sacrificing good swings, which means that his improvement in power production might be attributable to finding better pitches to hit. When you’re both flailing at pitches off the edges and letting meatballs go by, it’s hard to put up good power numbers.

Could Chourio’s carrying tool be punishing breaking balls? He’s hit sliders, curveballs, and cutters exceptionally well this year. He actually chases four-seamers as often as sliders, and when pitchers leave a slider in the strike zone, he’s phenomenally aggressive. He’s already clubbed seven homers, half of his total, on breaking balls this year. All seven were in the strike zone. Even curveball maven Charlie Morton got tagged:

So maybe this is it. He’s at the plate with a plan to send bad breaking balls into orbit. You might think that all of that desire to swing at bendy stuff means that those home runs mostly came when he was too aggressive outside of the zone. You’d be wrong. Five of those seven homers (I’d say bombs, but one was an inside-the-parker) have come in the last two months. It turns out that if you’re able to lay off pitches outside the zone, pitchers will come after you on your terms more frequently.

In the end, I’m not convinced that any of these skills are what I’ll think of first when I look at Chourio. Sure, he’s fast and powerful. Sure, he’s trying to detonate mistake breaking balls. He’s succeeding, too: He’s 12th in baseball in slugging percentage on contact when pitchers throw breaking balls down the middle, and 14th in xSLG. That’s not some cherry-picked statistic that doesn’t demonstrate real power, either: Aaron Judge, Vladimir Guerrero Jr., Teoscar Hernández, and Seager are the top four in that statistic. It’s a real skill – I’m just not convinced that it’s his best.

No, Chourio’s superpower was staring me right in the face all along. Matt Trueblood even tried to tell me about it. It’s encapsulated in all those changes he’s made over the past two months. His defining characteristic is youth. This guy is 20! Only 20 20-year-olds (fun coincidence there) have managed 300 major league plate appearances in a season since the turn of the century. Only 18, actually, because two of them are Soto and two are Bryce Harper, but I liked the round numbers. Chourio’s holding his own at an age when people just don’t do that.

The incredible improvement in his results as the year wears on? It probably has something to do with the fact that he’s adjusting to major league competition at a phenomenal rate. This time three years ago, he was in the Dominican Summer League. Last year, he was acclimating to life as a Biloxi Shucker, nearly five years younger than the average Southern League player. He got a cup of coffee in Triple-A Nashville (7.3 years younger than the league average) at the end of the season, but for the most part, he’s picking this all up as he goes.

Since July 1 — just so you know, I’m not using one arbitrary endpoint, I’m using two — Chourio’s hitting .331/.378/.517, good for a 150 wRC+. He’s tied with Seager with 1.5 WAR, in the top 25 among position players over that stretch. He’s striking out far less and still hitting for power. He’s 11th in the majors in steals, too. He’s batting at the top of the order for a playoff team and looks right at home there.

I’ll say it one more time: This isn’t normal. Players aren’t this good this young. Baseball at this level is a grown-up’s sport. Hitters need time to develop; even the guys we think of as phenoms mostly didn’t hit the majors before 21. We’re watching a meteoric talent establish himself in the major leagues. By next season, we’ll have more of an idea what Chourio’s best skill is. For now, it’s enough to marvel at how quickly he’s figuring it all out.