Joe Posnanski
May 20, 2017 · 5 min read

You may or may not know this, but there’s a little workshop over at MLB Advanced Media where brilliant people work day and night to discover the wonders of this little thing that we have come to call Statcast™. It’s a little bit like the control room for NASA in the movies “Apollo 13” and “Hidden Figures,” except …. no, actually, it’s exactly like the control room for NASA. They’re all wearing white shirts and thin ties, most of them have thick glasses, they smoke like chimneys and Mike Petriello, like Gene Kranz, blurts out every now and again: “We never misclassified a Kevin Keirmeyer catch, we’re sure as hell not going to do it on my watch. Failure is not an option!”

And Tom Tango saying: “I don’t care what about what anything was designed to do. I care about what it can do!”

Anyway, that’s how I’ve imagined it.

Statcast™ uses cameras and radar and goblins and tiny little birds equipped with James Bond spy gear to give us baseball data that would be previously unimaginable. Heck, it’s STILL unimaginable. Exit velocities. Launch angles. The speed of every moving object on the field. Precise leadoff distances. Pitching zones. But, and this is the crazy thing, the data really is the easy part. It is making sense of the data, using it to offer real insights into the game, this is the constant challenge. This has been the challenge since the beginning — figuring out what stuff is worth counting (say, strikeouts), what isn’t worth counting (number of times a player spits during a game) and how the counting enhances our understanding of baseball.

The vast majority of the Statcast™ data is meaningless, of course, because the vast majority of data in general is meaningless. It doesn’t matter how fast the left fielder is moving on a ground ball to second base, just as an example. But some of this stuff is pretty incredible.

And so we continue our “Fun with Statcast™” feature — this weekend we’re talking entirely about exit velocity. That’s it. Exit velocity is, as I’m sure you know, how hard a baseball is hit. Let’s take a starting point. I’m pretty sure this is just about as hard as a human being can hit a baseball.

That’s 120 mph. That’s a laser in non-technical terms. It was through the infield basically before the camera could even adjust to it. Now, the reason that was a single and not more comes down to the launch angle — that was a 5 degree launch angle. If it had been, say, 28 degrees, which is just about the perfect home run angle, well, it might still be going. But we’re not talking launch angles today. We’re talking exit velocity.

So that’s more or less maximum launch velocity — right around 120 mph. In the Statcast™ era, there have been only six balls hit at 120-plus mph, and realistically some of those might be Statcast™ errors. The top speed in a laboratory, if everything is absolutely perfect, is 120-or so mph. The more realistic top speed is about 114 or 115 mph.

And for the most part, you won’t see a ball hit at less than 40 mph. Here is a 40 mph exit velocity from the master:

So, with only a handful of exceptions, you are working within that 75 or so mph arc — 40 to 115, bunts to rockets.

So where does “good exit velocity “ begin? Tango likes to believe it begins at 88 mph, though he admits that might be the “Back to the Future” fan in him. I like to start at 92 mph because that is just about the minimum exit velocity required to hit a home run. Yes, there have been 62 home runs in the Statcast™ Era hit at exit velocities less than 92 mph — 62 out of 11,000, if you’re scoring at home — but just about all of them seem to be pulled or sliced right down the line, high balls that land just beyond the wall.

Here’s Mookie Betts hitting an 90 mph exit velocity homer over the Green Monster.

Here’s Justin Smoak yanking an 87 mph exit velocity ball over that short wall by the Pesky Pole on the other side of Fenway Park.

Here is what I think is the lightest hit home run in the Statcast™ Era. It belongs to Jarrod Dyson at 81.4 mph exit velocity.

So, basically, 92 mph is roughly where potentially good hitting begins. You will not generally do too well at 92 mph. The batting average on balls in play at 92 mph is just .261 — and you’re slugging just .347

But, add just one mph up to 93, and batting average goes up 25 points and slugging percentage goes up 50 points.

Here’s how batting average climbs based on exit velocity:

As you can see on the chart, batting average climbs at a pretty rapid pace until about 106 mph where it levels somewhat. That makes sense. Above 106 or 107 mph, you’re really just playing for distance … or you’re just showing off.

And here’s slugging percentage, again, climbing rapidly up to about 106 or 107 mph and then generally leveling off.

Now, remember, this is only measuring how hard the ball is hit. It is not measuring whether you hit the ball on the ground, hit it in the air or what direction you hit it. This is pure speed off the bat.

But just this is so consistent, with each mph above 92 mph adding to the value of the hit, that you could make a pretty persuasive argument that how hard you hit the ball is the most important factor in how successful you will be. If you hit a baseball 100 mph, you will get a hit about half the time. If you hit it 105 mph, you will get a hit about two-thirds of the time.

If you hit a baseball 100 mph, you will get an extra base hit about a quarter of the time. If you hit it 105 mph, you will get an extra base hit one out of every three times.

This is really interesting stuff. As mentioned, it’s hardly the whole story — but if you want to talk hitting, especially in 2017, you want to begin with exit velocity. Tomorrow, we’ll talk a bit about the hitters who are hitting the baseball the hardest in 2017.

Joe Blogs

The official blog of Joe Posnanski

Joe Posnanski

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Joe Blogs

Joe Blogs

The official blog of Joe Posnanski

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