For years, Statcast cameras (and before that, radar systems) have captured reams of data about every single play in every single major league game. We know not just the speed of a pitch, but its release point in three dimensions, where it crosses the plate, and the spin imparted on the ball. When a hitter makes contact, we know how fast the ball is moving when it comes off the bat, as well as the angle and the exact place it lands in (or out of) play. But there’s one thing we haven’t seen publicly – until now. Baseball Savant has released bat tracking data to the public, and it’s an exciting time to be analyzing hitters as a result.
The Statcast team was kind enough to provide us with an early look at things. So while you’re playing around with the new leaderboards and reading this excellent article by Mike Petriello that breaks down how this new data works, I wanted to give you a few early observations of my own, to spark some discussion and hopefully make you as excited about this new treasure trove as I am.
First things first: You’re going to love squared-up rate. You can think of this as a mathematical way of describing Luis Arraez. For a given swing speed and a given pitch speed, there’s a maximum possible exit velocity. That’s essentially what you’d get if you hit the ball on the sweet spot exactly on plane. If you’ve ever swung a metal bat, you know what this feels like. Statcast considers a ball squared up if its actual exit velocity is at least 80% of its maximum theoretical exit velocity. In other words, it measures whether you caught the ball flush.
Arraez is the best in baseball at this. He squares up roughly 44% of the pitches he swings at. Not 44% of the ones he makes contact with – the ones he swings at, period. There are no weak tappers in here, no jam shot foul balls or whiffs. To a degree that most players in baseball can only dream of, Arraez is an expert at getting the barrel of his bat to the baseball.
Why, then, doesn’t Arraez have gaudy power numbers? Remember that squared-up rate measures how often players get close to their maximum potential hit speed based on the speed of the pitch (out of their control) and the speed of their own swing. Their own swing provides the vast majority of the impetus here; the harder you swing, the more damage you can do assuming you square the ball up. And Arraez’s swing speed is last in baseball by a mile. His average swing is two miles an hour slower than runner-up Steven Kwan.
Those two names should suggest to you what’s going on here: Arraez and Kwan swing slowly on a relative basis, and they also square the ball up quite often. There’s an obvious correlation here. Those two are better able to adjust their swings to get the barrel to the ball because they aren’t swinging out of their shoes. They both have top-tier line drive rates and bottom-tier power. Again, this isn’t an accident. It’s a plan.
I lied to you a little up above, at least by omission. I said that squared-up rate is a mathematical way of describing Luis Arraez. That’s true. It’s not the most striking observation, though. That would be this: Juan Soto is absolutely ridiculous. Look at this scatterplot of swing speed and squared-up rate, courtesy of Savant:
Soto is third in squared-up rate in the majors. The guys ahead of him are Arraez (214th out of 214 in swing speed) and Nolan Schanuel (209th). Those guys are performing well above their swing speed because they get all of the ball with remarkable frequency. Then there’s Soto, who squares the ball up roughly as often as Schanuel (or Mookie Betts, fifth in squared-up rate) while boasting the 10th-fastest swing speed in baseball.
That’s just outrageous. Soto swings with as much force as Julio Rodríguez, Jorge Soler, or Willson Contreras. He gets his bat on the ball like the best line drive hitters in the game. He’s Arraezian with his contact but Ruthian with his power. Want to know why he’s slugging .541, striking out at the lowest rate of his career, and scalding line drives more frequently than he ever has? It’s because he’s hitting the ball right on the nose while swinging harder than pretty much everyone else. Soto has squared up 40.3% of his swings this year. The next-best mark among the top 25 hitters by average swing speed is Shohei Ohtani, who has squared up 29.6% of his own swings.
That brings us to another metric that’s now available: fast-swing rate. That’s how frequently a player swings at 75 mph or more. You can think of it, roughly, as the hard-hit rate of swings. To hit a ball hard, you have to swing hard. A full 66.2% of Soto’s swings are hard, while 11% of Betts’ are. Giancarlo Stanton is the league leader here, at a whopping 98.4%. That’s a mathematical description of the phrase “he doesn’t get cheated.” Stanton really does have the most raw power in the league, and he shows it on pretty much every swing. As David Adler noted, Stanton is the hardest swinger in baseball, and he leaves the rest of the field in the dust.
Of course, you can swing hard and still not hit the ball hard. You might miss it completely, top it, or get under it for a weak pop up. That brings us to blast rate. A “blast” is a simple construct. If you swing hard and square the ball up (per the above definitions of hard swing and squared up), that’s a blast. If you miss on one or both, that’s not a blast. End of story.
Soto doesn’t quite have the highest blast rate in baseball – he’s second by a hair behind William Contreras. If that doesn’t seem intuitive to you – Soto swings harder than Contreras and squares the ball up more often – you’re not alone. But think of it this way: Soto sometimes slows his swing down on a relative basis in pursuit of purer contact. He’s making the calculation that he’d prefer to swing a bit slower in some situations to maximize the odds of hitting the ball flush. However you look at it, though, these are gaudy numbers, for both Soto and Contreras.
The fun doesn’t stop there. Baseball Savant also reports swing length – the total distance traveled in three dimensions between the start of a swing and contact – and swords, which they define as a whiff where the swing was incomplete and where its speed is in the bottom 10% of all swings. It’s basically what you’d think – if a hitter gets fooled so badly that he ends up with his bat pointing out towards the pitcher, that’s a sword.
You can find some fun tidbits there. Arraez has the shortest swing in baseball, as you might guess. The longest? Javier Báez, which also tracks. Zach Neto has the most swords in baseball this year; he’s swinging hard, and when he gets fooled, he often fruitlessly tries to stop his swing. Stanton, on the other hand, doesn’t have a single sword. That’s connected to his gargantuan hard swing rate. Even if he’s fooled – and his 34.5% strikeout rate would indicate he gets fooled plenty – he doesn’t stop his swing. You can’t have a sword if you take a full cut, and he’s going all out on everything.
By using the toggles on these leaderboards, you can find some interesting data about switch-hitters. Want to know who’s a “true lefty” masquerading as a switch-hitter? Just measure swing speed differential. Elly De La Cruz, Cal Raleigh, Abraham Toro, and Josh Bell all swing at least two ticks harder lefty compared to righty. On the flip side, six players swing at least two ticks harder when hitting righty. There’s Anthony Santander, Luis Rengifo, Blake Perkins, and Jeimer Candelario, all of whom look mostly like the lefties, with swing speeds 2-3 mph faster from their dominant side.
Then there’s José Ramírez, who swings 4.5 mph faster as a righty. It’s no accident that his average exit velocity is 89.6 mph hitting right-handed and 88.2 mph swinging lefty. But even he pales in comparison to Ketel Marte. Marte swings 6.3 mph faster when batting from the right side. He’s second only to Stanton in swing speed from that side of the plate – wow! His lefty swing speed, meanwhile, is below average. His average exit velocity dips from 90.8 mph to 88 mph when he crosses the plate.
In case you needed a reminder that swing speed isn’t an all-in-one metric, Ramírez and Marte are great examples. Despite his swing speed disadvantage, Ramírez has better career numbers when batting lefty. Marte, on the other hand, is far better as a righty. There’s more to baseball than just swinging hard, and more even than just making solid contact when you do swing.
There’s plenty more to discover on these pages. I’ve only scratched the surface so far, and we’re going to keep getting more and more data, too. I’m curious to see how swing speed evolves as players age and whether some hitters can change their profile by swinging harder or aiming for more solid contact. And I haven’t even started looking at the pitcher side of things, which I think will be harder to wrap our collective heads around; obviously, pitchers have a lot less to say about how hard batters swing than the batters do. But either way, it’s an exciting time to be digging into baseball data, because an entire new avenue of investigation just opened up.
