Are we seeing the best defensive season by an outfielder, ever?

Pete Crow-Armstrong is a truly elite defensive outfielder. That is maybe the most obvious statement you’re going to read on this or any other baseball site this season, given the years-ago scouting reports that called him “the game's best defensive prospect” and the seemingly endless highlight-reel plays he’s made this year.

Of course he was going to have a strong glove. Of course he does have a strong glove.

The numbers say it (he’s No. 1 among outfielders in Statcast’s Outs Above Average, at +18). The eye test does, too. And when Chicago third-base coach Quintin Berry says things like “he’s the best player I’ve ever seen,” as he did before the season even began, it comes off as merely laying it on a little thick for a player on his own team, rather than completely absurd and laughable.

Yet while so much of the focus has been on his offensive breakout, on the (likely) 30/30 year that might have him post the best Cubs season since Sammy Sosa mashed 64 homers nearly a quarter-century ago, today we want to investigate a far more interesting question: What if PCA isn’t just the best outfield defender of 2025? What if he might actually be having the best outfield defense season that Statcast has ever tracked? Is this what peak outfield defense looks like?

Consider this: With 48 more Cubs games to go, entering this weekend's set in St. Louis, PCA had already set a new single-season record for most 5-Star catches in a season. (Those are the most difficult opportunities, the ones with a Catch Probability of 25% or less, with each chance evaluated based on time, distance, direction, and wall.)

Most 5-Star catches in a season (2016-pres.)

• 14 // Crow-Armstrong, 2025 (as of Aug. 8)
• 12 // Billy Hamilton, 2016
• 11 // Byron Buxton, 2017
• 10 // Jacob Young, 2024
• 10 // Adam Engel 2017
• 10 // Adam Eaton, 2016
• 10 // Max Kepler, 2016

Or this: PCA, by the first week of August, was tied for the 10th-best fielding season Statcast has on record with those +18 OAA, with the No. 2 slot (Hamilton’s +22 in 2016) easily in sight, and Buxton’s best-ever +27 in 2017 at least still on the table. If getting 9 more Outs Above Average feels like a lot, realize he’s had +6 OAA in a month twice already this year.

About those 5-Star catches, and how incredibly difficult it is to do what Crow-Armstrong is doing: Over the course of a season, an everyday outfielder will get something like 30 to 40 truly difficult opportunities. These "5-Star" chances, the ones that -- based primarily on time and distance, sometimes also direction and proximity to the wall -- are rarely ever made.

As of Aug. 6, outfielders this year had seen nearly 1,900 such opportunities and converted only 7% of them into outs. That’s because most of them look like this, mashed or well-placed balls that look nearly uncatchable. Because, more than 90% of the time, they are.

Most outfielders go an entire season without converting a single one of these extremely difficult chances, and that includes some highly respected defenders. Brenton Doyle, a two-time defending Gold Glover, went 0-for-24 last year, while the similarly well-regarded Michael Harris II was 0-for-29 in 2023. If the average Major Leaguer gets to around 7% of those chances, and the best of the best top out around 30% … well, look at the gap between PCA and the field here, looking back since 2016.

Best 5-Star opportunity conversion rate (min. 40 chances)

• 53% // Crow-Armstrong
• 37% // Jose Siri
• 30% // Jacob Young
• 28% // Kevin Kiermaier
• 28% // Keon Broxton
• 27% // Billy Hamilton

Converting these at such a high rate just doesn't happen, which is how he collected more of them by the end of July than anyone had done in the 10 seasons of tracking beforehand. Of those 14, some of them look exactly like you want them to, like on July 4, when he fully laid out to rob the Cardinals' Masyn Wynn of extra bases ….

… or on June 4, when he ran a mile (OK, 107 feet) before slamming into the wall at Nationals Park to rob Alex Call.

But plenty don’t, which is exactly what we wrote about way back in April when it became clear we were on the precipice of something special. That’s the real skill here, that PCA can make the most difficult plays look incredibly easy, simply because of his incredible speed and reactions before the broadcast camera has even turned to him. (While it’s tempting to judge outfield play on only the last second, remember how much of the play is decided based on what the outfielder has done before the ball is even over the infielders -- which you never see on television.)

His ability to get moving, very fast really breaks the eye test on defense. You watch this play against Elly De La Cruz earlier this week, and you might think it looks nice, with a mild slide at the end, yet it’s not something that most outfielders couldn’t get to. Watch it. Have an opinion.

It was a 15% Catch Probability. Nearly 9 times out of 10, fielders with that opportunity do not get there. What you can’t see is that PCA got a jump 10 feet better than average, which is saying that in the first three seconds, most of which is not visible on the broadcast, he got 10 feet closer to the landing spot than an average outfielder. Ten extra feet is enormous; that’s the difference between needing to dive or slide, or not have any prayer of catching it in the first place.

It was the same thing on this April play against Tommy Edman. It doesn’t look like much, but only because PCA turned a very difficult chance (10% Catch Probability) into one that seemed simple. Why? Because his jump was a massive 15 feet better than average -- again, work you can’t see on a broadcast.

So far as converting plays-that-almost-never-become-outs into outs, there’s no one in recent history who’s done it like Crow-Armstrong.

But what about the rest of the plays? There’s more to life than just the difficult ones. Because PCA is 4-for-5 on the next most-difficult plays (4-Star, the ones with 26%-50% Catch Probability), and 8-for-9 on the next most-difficult (3-Star), and on down the line, he’s turned 95% of the chances he’s seen into outs, across all difficulty levels. It’s the best rate of any player at any position.

Don’t forget, also: three of his rare miscues came because he lost a ball in the Wrigley Field sun and/or wind. (They were all scored as hits, coincidentally all with Cade Horton on the mound, which is why we use advanced defensive metrics. No, sun balls aren’t excluded; it’s part of the fielder’s job to deal with the conditions.)

Essentially, the only time when Crow-Armstrong has made a real, no-doubt mistake all year long was in late July, when he put himself in perfect position to corral this liner from Christian Yelich, and simply didn't squeeze the glove. It happens to everyone -- if rarely ever to him.

So yes, it’s already the most impressive defensive outfield season on record by some measures, and while it’s pretty hard to go back through history to compare to seasons from decades ago, remember this: As detailed last summer, there’s a fair bit of evidence that outfield defense is better than it’s ever been, as positioning has improved and the speed and skill level of outfielders has noticeably increased.

If that’s true, then it makes what PCA is doing even harder. It’s one thing to track down fly balls. It’s another to stand out “above average” when “average” keeps getting higher, which should be familiar to anyone who’s watched 95 mph fastballs go from notable to completely routine.

We haven’t seen anyone in this era of advanced tracking collect fly balls quite like PCA. There’s at least some chance we haven’t seen anything like this in a lot longer than that, too.