Everything (Or Nothing) Is Different About J.D. Martinez

If you’d just oblige me by briefly viewing one screenshot and four .gifs, I believe I’ll be able to neatly tie together all the different things that have been going on with J.D. Martinez this season. Let these five visuals serve as a reference point for the remainder of this post.

First up, the screenshot, revealing what the FOX Sports Detroit broadcast team decided to reveal about Martinez’s first at-bat, in graphic form:

Information gathered: the batter’s name is J.D. Martinez, and this is what his face looks like. J.D. Martinez flew out in his first at-bat. There is one out and nobody on in the fourth inning. J.D. Martinez is having an incredible season so far. The Tigers trail, 1-0. Dallas Keuchel is pitching. The umpire will need to look up before Keuchel delivers a pitch.

The umpire has looked up. Keuchel delivers a pitch:

It’s a first-pitch curveball, and Martinez does not swing his bat. You know who doesn’t see too many first-pitch curveballs when they’re batting? Pitchers. Because the pitcher who’s pitching doesn’t really care about the pitcher who’s hitting, so he throws him a first-pitch fastball. Nothing to worry about. J.D. Martinez? Lot to worry about. First-pitch curveball. No swing.

Keuchel, typically a low-ball pitcher, elevates a fastball, up-and-in. No swing.

Another fastball, elevated (but probably more than Keuchel wanted), another no swing.

Swing. Ground ball into the teeth of the shift.

OK. Now let’s try and tie this all together. Lot’s going on with J.D. Martinez this season.

We’ll start with the fact that Martinez saw four pitches and swung at just one. The bigger trend? Martinez has lowered his swing rate more than any hitter in baseball this season. It’s not that he’s reached Joey Votto levels of patience, it’s just that last year, he was one of baseball’s most aggressive swingers, and so far this year, he’s dialed it back dramatically, all the way down to below-average. Swing rate is one of the first statistics to stabilize, which makes sense, because, while influenced somewhat by the location of pitches seen, the decision of a swing is entirely up to the hitter. If a hitter really wanted to run a 100% swing rate, he could. Therefore, we can say with some level of confidence that Martinez’s swing rate has been an accurate representation of what’s happened, and is not being influenced by enough noise to make the number worthless.

The important caveat here is one expressed neatly by Russell Carleton over at Baseball Prospectus the other day, which is: just because a number is representative does not mean we should expect it to continue going forward. I’d be remiss not to point out that Martinez also has one of the most dramatic decreases in Zone%, to the point where he’s seen one of the lowest rates of in-zone pitches in baseball. Did Martinez likely enter this season with the mindset of taking a more passive approach? Yeah, probably. Is Martinez’s drastically changed approach likely being influenced by the way he’s been pitched? Yeah, probably.

Confusing right?

Now onto part two of the J.D. Martinez mystery, the thing that sent me down this rabbit hole in the first place. Last year, Martinez wasn’t much shifted. Could be because the league hadn’t seen enough of him yet. Could be because of how adept he is at hitting the other way with authority. But even with that opposite-field power, Martinez still pulled an above-average number of his balls in play, overall, and pulled nearly 70% of his ground balls last season. Despite that, he was only shifted in 7% of his plate appearances, according to Baseball Info Solutions, or about as often as Joe Mauer. A correction was due.

And the correction has arrived. So far this season, Martinez has been shifted in a whopping 41% of his plate appearances — including the one we saw above — or about as often as Prince Fielder. It’s the second-largest shift increase of any qualified hitter in baseball. Martinez hit .319 on grounders last year, and for a pull-happy slow dude, that number is way too high. Teams probably aren’t going to take away Martinez’s dingers, so the very least they could do is take away some of his ground-ball hits. No more easy singles for Martinez this year.

Except, now that Martinez is seeing teams attempt to take away his ground ball hits with shifts, this funny thing’s happened:

By now, you’re well aware of the mechanical adjustment made by Martinez upon his arrival in Detroit that got more lift in his swing and allowed him to tap into his raw power and become the monster he is today. Last year, Martinez put the ball in the air more often than all but nine qualified major-league hitters. Already one of the most extreme air-ball hitters in baseball, Martinez has nevertheless had, once again, one of the league’s largest increase in air ball percentage, tacking on 11 points to last year’s total. Three-quarters of Martinez’s balls in play have been in the air.

Except, you saw how Keuchel tried to elevate on him. That’s because everyone is trying to elevate on him:

Martinez has seen one of the 10 largest increases in upper-half pitches of any qualified hitter in baseball, relative to last season. As teams are shifting Martinez to take away his ground balls to the left side, they’re also pitching him higher than ever, and he’s “beating” the shift by hitting it over the heads of the infielders, and hitting it with authority. Is Martinez’s increase in air balls a likely reaction to the shifts he’s seen? Yeah, probably. Is it also probably influenced by the pitches he’s seen? Yeah, probably. Is there also likely some noise involved? Yeah, probably.

So what did we learn from this? We learned that there’s a lot going on with J.D. Martinez, but we also learned that we don’t know anything. At the very least, we learned what the teams are doing to limit Martinez: They’re shifting him, they’re avoiding the strike zone, and when they do come in the zone, they’re trying to attack his weakness more. What did we learn about Martinez? Maybe he’s trying to be more passive. Maybe he’s reacting to the shift by trying to put the ball in the air more. What did we learn about how the league’s new approach toward Martinez is working? It’s not. Martinez is killing it. What did we learn about how things might play out in the future? Nothing. We learned that this game is impossible.