After much anticipation and salivation, Major League Baseball has begun trickling out tidbits from its revolutionary and proprietary STATCAST system, which tracks in real time the flight of baseballs off players’ bats, and routes defenders take to batted balls.  This data, many think, will help close gaps in baseball analytics, and lead to an even more comprehensive understanding of how the game works, and how to measure a player’s true value.

To date, this fascinating information has been available only during live game broadcasts, and replays on MLB.com. The most voluminous set of STATCAST data readily available for consumption, thanks to the folks at Baseball Savant, is batted ball velocity.  This, it would seem, gives us a measure of how hard a ball is hit, by telling us how fast the ball is traveling when it leaves a hitter’s bat.  The numbers are fun to poke through, and seem at the outset to confirm what we already know, that guys like Giancarlo Stanton, Paul Goldschmidt, and Pedro Alvarez hit the ball not only very far, but very hard.

There, however, clearly some wrinkles in the linens.  Jeff Sullivan at Fangraphs has already pointed out some inconsistencies in the data, with questionable readings of over 100 mph on a series of Hanley Ramirez ground-outs, and an Anthony Rizzo bunt likewise registering in the three digit range.

With that in mind, I took a closer look at the Batted Ball leaderboards for myself, and found a few more inconsistencies to muddy up the waters.

For starters, let’s take a look at the Top 10 hitters in average batted ball velocity: (A caveat here… This was compiled a couple weeks ago, so some of the rate stats might have changed, but it serves as a snapshot in time.)

HIGHEST AVERAGE BATTED BALL VELOCITY (min 60 AB)

1. Giancarlo Stanton 97.47
2. Joc Pederson  96.24
3. Jorge Soler  95.22
4. Yasmani Grandal 94.61
5. Ryan Braun 94.56
6. Logan Morrison 94.29
7. Alex Rodriguez 94.28
8. Carlos Gonzalez 94.02
9. Paul Goldschmidt 93.96
10. Pedro Alvarez 93.79

No real surprises there, save maybe Logan Morrison, who isn’t generally thought of as a slugger, but once did have a decent pedigree as a prospect.

There is different data available for different players, and if you go up to 100 at bats as a minimum, you get a few more familiar names, all of which are unsurprising.

HIGHEST BATTED BALL VELOCITY (min 100 AB)

1. Josh Donaldson 94.09
2. Miguel Cabrera 93.95
3. Prince Fielder 93.01
4. Mike Trout 92.65
5. Hanley Ramirez 92.6

Based on the high-velocity results, one might believe the other end of the spectrum, the lowest batted ball velocities, would feature the slappier, punchier hitters in the game.  Your shortstops and middle infielders and the like.  And behold…

LOWEST AVERAGE BATTED BALL VELOCITY

1. Ichiro 80.9  287/342/337 (301 BABIP)
2. Billy Hamilton 81.9  214/263/336 (241 BABIP)
3. Alberto Callaspo 81.4  211/305/267  (214 BABIP)
4. Omar Infante 82.6  254/260/377  (290 BABIP)
5. Jose Iglesias 82.71   345/400/445  (370 BABIP)
6. Dee Gordon 82.72  406/430/497  (457 BABIP)
7. Alcides Escobar 83.33  303/341/402  (324 BABIP)
8. Johnny Giavotella 83.75  274/326/342  (310 BABIP)
9. Matt Joyce 83.79  143/180/219 (177 BABIP)
10. Jimmy Rollins 83.94  196/277/348  (213 BABIP)
11. Zack Cozart 84.01 300/358/525 (309 BABIP)
12. Yadier Molina 84.45  302/350/364  (351 BABIP)
13. Michael Bourn 84.48  233/315/302 (300 BABIP)
14. Didi Gregorious 84.59  204/269/241 (256 BABIP)
15. Charlie Blackmon 84.59  279/331/463  (340 BABIP)

I’ve included some rate stats along with BABIP here to get an idea of the level of success these hitters had, given the relative low velocities of their batted balls. While not exactly hitting lasers around the park, these types of hitters have had some success.  You have a couple high-BABIP guys like Dee Gordon (.457!), Jose Iglesias (.370) and Charlie Blackmon (.340), but the others are pretty well within the range of normal.  Not surprisingly, the higher BABIPS generate the better rate stats, but most of these guys, with the exception of Yadier Molina and Matt Joyce appear to be the scrappy, slappy hitters you might imagine they’d be.

The real confounding velocity guys are the ones in the middle of the pack.  Observe…

THE MIDDLE

1. Kris Bryant 88.77
2. Jacoby Ellsbury 88.75
3. Joe Mauer 88.74
4. Joey Votto 88.73
5. Chris Coghlan 88.62
6. Denard Span 88.57
7. Kevin Kiermaier 88.5
8. Brett Lawrie 88.49
9. Alex Gordon 88.48
10. Brian McCann 88.43
11. Anthony Rizzo 88.40

OTHERS

1. Jose Altuve 86.56
2. Angel Pagan 85.96
3. Dustin Pedroia  87.39
4. Neil Walker 87.41
5. Brandon Moss 87.98
6. Stephen Vogt 87.84

And this is where you begin scratching your head.  I’ve personally seen Anthony Rizzo hit some bombs.  Just no doubters.  And then there’s the Paul Bunyanesque Kris Bryant slotted in just barely in front of Jacoby Ellsbury.  Brandon Moss, Steven Vogt, Alex Gordon, and Brian McCann all trail DENARD SPAN in batted ball velocity. Denard Span!

I’m not real sure what’s going on.  There’s clearly something missing here.   While high average velocities off the bat seem to correlate pretty strongly with big, meaty power guys and low velocities seem to give us the guys we’d expect, the hitters who sit well-below 90 mph are hard to figure.  Because several of them are very good hitters, with good power.  Maybe it’s the difference between 70 and 80 raw power.  But there’s no clear line of demarcation.  Could 88 mph and above signify 65 power?  90 and above 70?  95 and above 80?  Perhaps it’s game power versus raw power?  That would seem to explain Kris Bryant earlier this year.

I have, sadly, no real conclusion, other than to observe that there clearly needs to be further study of this as a statistical measure of performance.  There’s definitely something there, but it seems like something needs to be added to it, perhaps some kind of metric that hasn’t been created yet.  The possibilities are fascinating, and I look forward to the next leap in analysis!