The First Pitch Strike Game

The best result from a first pitch? Has to be a dribbler to the mound, right? We spend all this time chasing the swinging strike and drooling on triple-digit velocity, and there’s a future Hall of Fame pitcher who made his living getting first-pitch sawed-off million-hoppers to the second base side — Greg Maddux.

But if you’re not Greg Maddux, the first strike is the nexus for a game of cat and mouse. We’ve found that throwing a first-pitch strike is one of the best ways to get your walk rate down. But if the league throws too many meatballs on 0-0 counts, batters should swing more. It might be the best pitch they see. If the league then throws fewer strikes for the first pitch, batters would find themselves looking more. I don’t know if it’s game theory, but it’s certainly a theory about this game.

But the first-pitch out was the beginning of this string. J.D. Gentile lamented the drop in first-pitch outs recently, even as he showed that Greg Maddux was, indeed, the master of this craft. In that piece, Gentile brought up the batting average on balls in play on the first pitch:

It might be easy to say, hey, that’s where first-pitch outs went, but to Gentile’s credit, he does point out that league BABIP also jumped at the same time. Let’s see those two effects on top of each other, no?

Apologies for that. Anyway, two things might be visible in that mess. One is that something strange happened in 1992, maybe. That’s the only year where the league BABIP and first-pitch BABIP were so close. The other thing is that, while the two have tracked each other well, the BABIP on the first pitch is usually about fifteen-to-twenty points higher than the league BABIP.

That seems like a decent reason to swing at the first pitch. It’s going to be a strike, and (probably since it’s going to be in the strike zone) it’s more likely to find grass than the average pitch. Was the league-wide first-pitch swing rate steady over this time? Thanks to Jeff Zimmerman, we have this answer:

Wait what. We’re in the golden age of first pitch BABIP, and batters are swinging at fewer and fewer first pitches? Pitchers must be throwing it outside the zone more often in response, right? They must be reacting to the BABIP, playing that first-pitch strike game, adjusting to the adjusters. Right?

Oh come on now. Something happened in 1996, yes. It looks like that jump in first-pitch swing rate wasn’t brought on by BABIP changes, too — 1992’s small separation between first-pitch BABIP and league BABIP might have sent the swing rate down, but in 1996, the difference between the two BABIPs was less than it was before 1992.

Maybe instead it was the first-pitch strikes that made a difference in 1996. Maybe that year, front offices looked around the league, saw that first-pitch strikes were down, and sent that information down to the field, where coaches passed it on and batters decided to swing more. And then pitchers maybe saw what was happening, and the batters swung less often in order to correct back to their correction.

But whatever possible here-and-there that happened in the late 1990s didn’t last, and now batters are swinging less at first pitch strikes, even though there are more first pitch strikes. It doesn’t make any sense.

There are some confounding issues that might be messing up these graphs. In 2000, the American League and National League umpires merged their crews. In 2001, a larger strike zone was implemented along with an evaluation system. Those factors might explain some of the oscillation to the left of the graph.

But on the right of the graph? You still see a fat BABIP, and some of the best first-strike percentages the modern game has seen… and some of the lowest first-pitch swing rates we’ve seen recently. It makes sense from a pitcher perspective — if they aren’t going to swing, you might as well get on the way to a strikeout instead of slipping towards a walk.

Hitters? Don’t know why they aren’t swinging more. After all, Greg Maddux is out of the game.