The Evolutions Keep Coming: How Pete Crow-Armstrong Stayed Ahead of the Adjustment Curve

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The first remit of the big-league batter is to be on time for the fastball. It's the bare minimum for any player hoping to stick around in the majors. It's necessary, but not sufficient, because there are plenty of guys who can do it. The real challenges are to do it without giving up your power by shortening your swing too much; to define 'on time' in a way that produces batted balls with real value; and to do it while still covering slower pitches, like sliders, curveballs and changeups. The name of the game is conviction; you have to swing with confidence to hit the ball with authority. Get overconfident, though, and all you've done is make yourself vulnerable to constantly being fooled.

It's this balance that Pete Crow-Armstrong has struck with ferocious perfection over the last four months. In fact, he's been moving steadily toward that perfect balance not only since the middle of 2024, but even since the 2026 All-Star break. He's a unique case to study in this regard, because he forces us to answer an interesting question: Where the hell did the erraticism of his batting profile go, exactly?

Real improvement is possible, of course. We live in the Golden Age of player development. Teams, independent facilities, and players themselves have gotten far better at adjusting and leveling up than they used to be. Still, there's a version of science's law of conservation of mass that applies to baseball, too. To borrow from a different discipline, there's no such thing as a free adjustment. Everything requires a tradeoff. When we're talking about hitters, that usually means trading contact for power (or vice-versa); being more patient but striking out more because you end up in deeper counts; or pulling the ball less often so as to wait longer and make better swing decisions. Add more tilt to your swing so that you can handle breaking stuff better and use the opposite field more, and you might be susceptible to the high fastball. Flatten it to cover the heater, and you're likely to hit more grounders and more pop-ups.

How, then, is what Crow-Armstrong is doing possible? Consider this comparison of his last three seasons, and it's hard to see where he's traded anything for this massive change in production.

Yes, he's striking out more, but it's a tiny bit more. That really doesn't count as a tradeoff—not when your walk rate has moved three times as much as your strikeout rate, and there's so much more production on balls in play, to boot. He's lost a tiny bit of speed and arm strength, as virtually every player does even throughout their early 20s, but we're not seeing him become materially less lithe in order to build the strength and generate the power we've seen from him.

The Squared-Up% line is the only other one in which he's not currently at his best. At first, that looks like a small, even negligible difference, too. In fact, though, that's where he's made the hidden, vital tradeoff that has unlocked this version of him. Let's talk about how.

First, you need to know what Squared-Up% is. It's simpler than it will sound, at first, so hang with me. To determine whether a ball is Squared-Up, by Statcast's reckoning:

Collect the swing speed, the pitch velocity and the exit velocity for any given batted ball.
Using a physics equation we laypeople don't need to memorize, find the maximum exit velocity that was possible on that pitch, given the swing speed and the pitch velocity.
Divide the actual exit velocity by the maximum possible one.

Then, to get to their Squared-Up%, take the number of batted balls on which the steps above return a result over 80%, and divide it by the player's total number of batted balls. That's not quite arbitrary, but it's a line they settled on; another way to report the same number would be to stop after the three steps above and take the average result on all their batted balls as the player's Squared-Up rate. There are pluses and minuses to each; it's hard to create a perfect version of this stat.

For reference, here's a chart showing Crow-Armstrong's Squared-Up rate (over rolling 100-plate appearance windows) in that second way, throughout his career. It tells the same story: he's squaring it up a bit less this season than in the past.

Ok, so that's what this number is. Why is it such a key to understanding Crow-Armstrong? Because it reveals what he's done to go from a hacktastic, erratic slugger to a more lethal one, even though it demonstrates less precision on his part. In the past, Crow-Armstrong was swinging under a bit more control—not in terms of whether he swung, unfortunately, but in terms of where and how he did so. He has slightly above-average feel to hit, and early in his career, his approach was geared toward using it. He wanted to pull and lift the ball, but he wanted to do it by being accurate with the barrel.

Over the offseason, Crow-Armstrong and the Cubs decided to sacrifice that restraint for more bat speed. That's been the key to his season, and it's why his Squared-Up rate both betrays the underlying tradeoff he made and, in the grand scheme, doesn't matter very much. If you swing the bat 70.6 MPH on average, you need to square it up fairly well to hit for power. If you swing it 72.7 MPH, you have a bigger margin for error, but you're not yet at the point where you can do much damage without hitting it on the screws. If you swing it 75.0 MPH, though—and, at this point, Crow-Armstrong is really swinging it even faster than that most of the time—you've reached the point where your mishit balls still pose a threat.

Since the All-Star break, Crow-Armstrong has put 13 balls in play on swings that were 81 MPH or faster. That's as many such swings as he connected on in his entire career before that. His bat speed is through the roof, and specifically, his bat speed on swings that result in balls in play has risen sharply. That means that he can miss the sweet spot a little bit and still hit it hard and far.

Don't get me wrong. Any hitter is still going to find most of their value on batted balls on the swings that connect cleanly with the ball, resulting in Squared-Up contact by the Statcast definition. Crow-Armstrong just doesn't rely as much on that as most elite sluggers do. Here's a comparison of the timing profiles on hard-hit balls for the best offensive weapon of each of the last three seasons: 2024 Shohei Ohtani, 2025 Aaron Judge, and this year's version of Crow-Armstrong.

Notice that, compared to the other two super-sluggers, Crow-Armstrong is exactly on time (the center panel) more often on his hard-hit balls, but more likely to hit it in toward the handle (left panel). Exit velocity is controlled most strongly by that left-hand image; getting the ball in the center of the barrel (rather than off the end of the bat or on the label) is the surest way to produce hard contact. But that's less true for Crow-Armstrong than for most hitters. He needs to be on time, but not as much on barrel. Balls hit either direction from the center of the barrel by more than about one baseball (2.9 inches) are rarely going to register as Squared-Up. But if you hit that ball with the bat square to it, and if you're on plane with it and/or working uphill at contact, and if you swing the bat 80 MPH as you do so, you don't have to produce Squared-Up contact to hit a screaming double, or even a homer.

So, we circle back to what I said at the very beginning of this piece: a hitter's remit is to be on time for the fastball. That part is even truer of Crow-Armstrong than of most players, even though other general rules about a hitter's process don't seem to apply to him. That's exactly what Crow-Armstrong has done this season. Here's his set of swing timing visuals for each of the last three seasons, on four-seamers and sinkers only.

Unsurprisingly, we see him being much more consistently on time this season, and late less often. The tradeoff here is that he's getting the ball in on the label much more often. We've already talked about this a bit. It's what he had to sacrifice to get on time by swinging faster, without being too early on the breaking stuff. Speaking of which, here's the same set of visuals for breaking pitches.

He's early on spin as often as ever, but notice how he's moved into the sweet spot more often in terms of centering those pitches on his barrel. He probably wouldn't put it quite this way, but his swing is now designed to attack the fastball with brute force, worrying about colliding with it at speed but not about being precise with the barrel—while, because it works out given the locations and shapes of the respective pitches most of the time and because of the arc of his swing, he's getting more value on breaking pitches by getting from that inefficient contact point to an efficient one.

This takes great pitch-recognition skills. It takes a hitter with above-average feel, which was always lurking in his skill set before, underutilized. It also takes a flexible approach, because once you show opponents that you can do all of this, they're going to adjust to you, too. Thus, even within the season, Crow-Armstrong is learning to time hurlers up slightly differently, to combat the different ways he's being pitched. Here are the same visuals as above, returning to fastballs, but this time, the breakdown is month by month throughout this season, rather than season by season.

August marks a departure from what he did in the season up to that point. Crow-Armstrong moved slightly back toward letting himself be late on the fastball—not quite to actually being late, as he too often was in the past, but toward it. By letting the heater travel that tiny bit more and clipping the bottom half of it a bit more (right-hand panel), he was putting himself in a less exploitable position against softer stuff. These kinds of tweaks have kept him from being solved throughout what first looked like an incredible hot streak. Now, instead, it looks like a durable Hall of Fame breakthrough.

Back in mid-May (just before he implemented the set of adjustments that lit the fuse on his rocket to superstardom), I wrote about the way Crow-Armstrong's newfound bat speed was actually getting in the way of being productive. That was because he hadn't learned to time pitches up right, given how much faster he was moving the bat; he was early too much. That was leading to lots of ground balls and lazy fly balls. To capitalize on swinging with such abandon, he needed to be on time more consistently. Even in noting the deficiencies, though, I said the following:

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This isn't bad news, really. There are worse ways Crow-Armstrong could be getting to his underwhelming .675 OPS, in general. There are even worse ways he could specifically be suffering from his own increase in bat speed. Instead, he's still in control of his swing, and if anything, his swing decisions have improved. Swinging faster still should be good for him, in time. For now, though, he's yet to figure out how to alter his timing in a small enough way to compensate for being early, without falling into the trap of being late, as he was for some stretches last season. It's not easy to make that adjustment, small though it might sound. There are no guarantees that Crow-Armstrong will lock in and start producing a .900 OPS again any time soon. There is, however, a real chance of that—because his bat speed is up, and bat speed is good. It's just a matter of paying the cost of it.

What needed to happen was not more collision efficiency in Crow-Armstrong's swing, exactly, but better timing. His bat speed boost had rendered him capable of hitting it hard even when he didn't line everything up perfectly, and his unique directionality profile—the orientation toward pulling and lifting that made him an unexpected slugger even last year—meant that that hard contact was often going to be in the air, headed to the part of the park it would have a chance to leave. He just had to be on time, in order for that to happen.

Shortly after that, Crow-Armstrong moved closer to the plate, altered his setup in the box, and—thanks to those changes, which forced his lower half to move differently as he loaded up for each hack—found his way to being on time. The rest is, without hyperbole, history.

Moving closer to the plate exposed Crow-Armstrong to a little more risk of catching the ball up toward the handle from the sweet spot, of course, but as long as he was on time, that didn't matter too much. What's happened, ultimately, is that his much-improved swing decisions—a trend that started early this season, after he flipped the turbo switch on the swing but before the setup and timing changes—and his bat speed increase allowed him to make a 1-for-2 trade. He gave up efficiency of contact, for both more contact (especially more of it in the air and to the pull side) and more bat speed.

Only a player with a perfect confluence of enormous talent, tenacity, intelligence and a great support system could pull this off. Crow-Armstrong owes much to his teammates and coaches, but in evolving this way—in avoiding a compensatory slump of any real length as he's been adjusted to and tested in new ways by opponents—he's showed the depth of his genius and his desire, as well as his ability. This is the most impressive season by any baseball player in at least 60 years, not only because of the physical prowess on display, but because the player who's achieving it had to be so diligent, obsessive and adaptable to do so.