Swinging at first pitch and game theory

I’ve been looking at some of the changing trends involving the first pitch of the batter-pitcher match-up for Beyond the Box Score over the past few weeks, with far more enthusiasm than I probably should. It’s a part of the game that I find fascinating, and the more I look into it the more oddities seem to be revealed.

For instance, I’ve noticed that BABIP on the first pitch has been mysteriously on the rise over the last two decades, and that only once-in-a-lifetime pitchers like Greg Maddux were particularly adept at inducing outs in 0-0 counts.

Until today, though, I’ve mostly dealt with first pitch trends from the pitchers’ perspective. This morning I want to look at first pitch balls in play for unique types of hitters, trying to determine which types tend to succeed more often when putting the ball in play early in the count.

Taking advantage of a patient hitter

We are aware that certain ballplayers have reputations as unusually patient hitters and will rarely swing on the first pitch. In my years as a baseball fan, Joe Mauer or Kevin Youkilis as having a similar type of approach at the plate.

We might suspect, then, that opposing teams travel with scouting data on how seldom these batters hack in 0-0 counts and would apply this information to their advantage on the mound. If we’re fairly certain Youkilis and Mauer are going to balk at the first pitch, why bother throwing anything off the plate? After all, the differences between the outcomes of an 0-1 count and a 1-0 count are enormous. In 2012 alone, it was ultimately the difference between an .822 OPS and a .612 OPS for major league hitters on average. That first strike is critical.

This is where the power of game theory comes in. If, for instance, Mauer and Youkilis know that they are far more likely to get a meatball to begin their plate appearance, how well do they fare on that rare occasion when they do swing at that first pitch?

To answer this, I looked at wOBA on first pitch balls in play including home runs (or wOBA/CON for “wOBA on contact”) for all hitters with at least 2,500 plate appearances since 2002. I then compared their wOBA/CON on first pitch against their wOBA/CON in all counts.

The hitters who put the ball in play least often on the first pitch are mostly players you would probably expect, that is, players with prominent reputations for having a patient approach at the plate:

Batters with lowest first pitch BIP% since 2002

For the most part, this is a group of above-average hitters who are well-known for their ability to work counts and wait for “their pitch.” We can see that, as a whole, their wOBA/CON on first pitch was significantly higher than their overall rates. In fact, the difference between the weighted average of their first pitch wOBA/CON and their overall wOBA/CON was a healthy .024. That may seem impressive, but we have to remember that the league as a whole generally has an advantage when putting the ball into play on the first pitch.

These are the league rates during that same time period, 2002-2012:

On average since 2002, major league hitters have enjoyed a .013 spike in their wOBA/CON when putting the ball in play on the first pitch. So Mauer, Youkilis and Co. seem to gain an advantage of .09 wOBA/CON over the rest of the league when ambushing a pitcher on 0-0.

This advantage for the more patient hitters seems to hold true for onlythe most elite members of their kind, however. Hitters with the top 50 fewest first pitch balls in play percentage did not seem to hold much of an advantage over the league and actually scored a hair below league average with just a .010 delta in their weighted average.

In fact, the some of the most aggressive hitters over the last 10 years actually seemed to fare far better than some of their patient counterparts when swinging on 0-0 counts:

Batters with highest first pitch BIP% since 2002

So we have some strange things going on here. Certain notoriously patient hitters like Mauer, Jack Cust, and Jayson Werth appear to be demonstrating some ability to catch pitchers by surprise by swinging on 0-0. But for others, like Nick Swisher and Youkilis, there doesn’t seem to be much of an effect. Furthermore, some of the players from our group of 10 highly-aggressive hitters were just as fortunate in first pitch BIP situations, while the group as a whole improved exatly the same amount as the league (.010):

It would seem, then, that success with balls in play on first pitch is mostly random, perhaps with a few outliers where game theory might come in to play. But if the effect exists, it exists only on that extreme end of the spectrum. For example, If we look at all 302 hitters from 2002-2012 with at least 2,500 plate appearances, we can see that their success in putting the ball in play in 0-0 counts is not at all dependent on the frequency with which they occur. The relationship between first pitch balls-in-play percentage and wOBA on contact for all 302 hitters was a non-existent r = .0004:

Unfortunately, there is no overwhelming evidence that hitters who swing less often at the first pitch gain an advantage by occasionally shocking the opposition and jumping on an 0-0 meatball. But there may be enough to suggest that for certain hitters whose first-pitch habits are extremely conservative, the occasional ambush may produce a small, marginal advantage over the rest of the league. We may just need more ways to test the issue.

I’d appreciate your comments on any way this line of inquiry might be improved, or what possible explanations you might have as to why game theory in 0-0 counts doesn’t seem to pay off with the significant dividends one might expect. Are hitters simply too uncomfortable departing from their well-defined, finely-tuned approach at the plate? Does jumping on the first pitch just feel too unnatural to them?

I’d like to hear your thoughts.

References & Resources
All data includes post-season PA.
Thanks to retrosheet and Fangraphs “GUTS” for providing data used in this article.