The anatomy of a bad-ball hitter

Bad ball hitters are great, because things like this are great:

Unexpected things are great, and Vlad Guerrero hitting a ball that bounced two feet in front of the plate is pretty unexpected. In the video, Chris Tillman looks like he's probably mad (with good reason, that was a fine pitch for a 1-2 count), but everyone else is into it. Orioles Manager Dave Trembly was quoted in the MLB.com game story as saying "Gosh darn--that's the old stickball play. That was something." Gosh darn indeed! (The game story also used the phrase "a new low", so just a great effort all around that day.) Bad-ball hitters are weird, and weird is fun.

Vlad is definitely the most notorious hitter of this type, but his legacy is carried on by several guys today. They're a fascinating bunch, because their process is so different from what we're used to seeing. On the one hand, yes, Vlad hit a single on that pitch, and he was known for getting hits on pitches other hitters would be nowhere near. On the other hand, is he really not better served by taking those pitches? How does one become a successful major-league hitter either lacking or completely ignoring pitch discrimination?

One potential explanation is that hitters of this type have the ability to do lots of damage on contact, so it's worth it to swing freely. These are players like Evan Gattis and (probably) Joey Gallo, who have the power-on-contact to make up for all the times that they miss. Those players aren't really what I would call a bad-ball hitter, since they swing and miss so much. Part of what makes guys like Guerrero, or more modern players like Pablo Sandoval, singular is that they not only swing at lots of balls, but make contact with lots of them. The players in this archetype tend to have decent power, but not off-the-charts. So how do they develop into such free swingers?

My theory is that players of this type have a more gradual drop-off in production from swings at balls in the strike zone to swings at balls outside the zone. Through some skill, probably a combination of bat control and pitch recognition, these hitters can not only square up pitches other hitters don't, but also do nearly as much damage, making it less worthwhile for them to wait for a better pitch. If a player can make contact on every ball outside the zone, but can only hit weak grounders, he's not going to last long with a free-swinging approach. Similarly, a player who can hit singles on pitches outside the zone, but has prodigious power on pitches inside the zone, might survive as a player if he swings at lots of out-of-zone pitches, but would likely benefit from a more discriminatory approach. Perhaps bad-ball hitters don't lose a lot by swinging at balls, nor do they gain a lot by waiting for strikes.

So this seems to make at least intuitive sense, but what does the data show? I pulled all hitters with at least 1,000 plate appearances from the start of 2013 through Monday night, a sample of 175 hitters. The average rate of swings at pitches outside the zone was 31.2 percent; the average rate of contact on those swings was 68.3 percent. There are eleven hitters with a out-of-zone swing rate over 35 percent and a out-of-zone contact rate over 75 percent: A.J. Pierzynski, Adeiny Hechavarria, Adrian Beltre, Alcides Escobar, Erick Aybar, Jean Segura, Jose Altuve, Pablo Sandoval, Robinson Cano, Salvador Perez, and Yadier Molina. These are our bad ball hitters.

By definition, they make contact on a lot of pitches (the average overall contact rate for these hitters is 85.7 percent, compared to 80.8 percent for the whole sample), so I'm going to look at outcomes on contact. Using Brooks Baseball, I calculated the ISO of each of these hitters on balls outside the zone and the ISO of balls inside the zone.

BIP=balls in play

Taken as a group, these hitters' ISO when making contact on pitches out of the strike zone was almost exactly half of their ISO on pitches inside the zone. It's notable again that none of these hitters have huge power; the closest are probably Adrian Beltre and Robinson Cano, but the relative dearth of sluggers supports the idea that these batters have less to lose when swinging on pitches outside the strike zone, relative to their peers.

What about those peers? How does that 49.6% ratio compare? I identified a group of "anti-bad-ball hitters", players with a swing rate on pitches outside the zone of less than 25 percent and a contact rate on those pitches of less than 65 percent. They are: Adam Dunn, Austin Jackson, Christian Yelich, Dexter Fowler, Mike Napoli, Russell Martin, and Shin-Soo Choo, seven in total.

What's really interesting to me is the mix of players in this group, ranging from high-power, three-true-outcomes guys like Dunn and Napoli to players whose hitting game is focused around speed and contact like Yelich. This supports both the reasons why someone may or may not develop into a bad-ball hitter. On the one hand, guys of the first type are giving up too much by swinging at a ball outside the zone. They might run into a single a decent amount of the time, but their game is built around doing lots of damage on contact, and they can't waste that on a bad pitch. Players of the second type are also trying to make the most of the contact they make, but their strategy is to slap lots of line drives and ground balls and beat out hits, and a swing at a ball is less likely to produce the kind of contact they need to reach base.

What do their ratios look like?

Indeed, they're much lower, and that's before taking into account their increased whiff rate on swings at pitches outside the zone. Clearly, this group loses a lot more when they go outside the strike zone, so it's no surprise to see them do it less.

All together, this seems like a simple argument. But this is showing more than just "players who swing at pitches outside the zone are probably pretty good at hitting those pitches." What's important is the ratio of their out-of-zone performance to their in-zone performance. To me, this suggests that perhaps the notion of players in the bad-ball category having bad eyes might be overstated. It's not that they don't recognize balls, but that they have a different hitting zone than most batters, and as such "ball" isn't the same as "a bad pitch to swing at" for them. That's not clear from this, however, just wild speculation.

Finally, it's worth pointing out that these players are freaks. This analysis doesn't prove causation at all--it could be that the only players who survive with lots of swings and contact on balls are players with relatively equal in-zone and out-zone production. In any case, it's clear that trait is one of the things that makes a player into a bad-ball hitter, and as such, it should be encouraged and developed in every way possible, because these kinds of players are the best.

. . .

Henry Druschel is a Contributor at Beyond the Box Score. You can follow him on Twitter at @henrydruschel.