Adam Eaton Is Up to Something

Pardon me; I don’t mean to interrupt your afternoon. If you’re here, though, you might well be a bit curious about Adam Eaton. Which is good, because I am, too! To get started, you know those player caps we have on most pages? The profiles and quick opinions, I mean, written by various FanGraphs authors. They’re written during the winter, providing brief player analysis, and here’s a link to Adam Eaton’s page. I’m going to pull a little excerpt. This isn’t intended to pick on Chris Cwik. Anyone would’ve written the following.

Since Eaton isn’t going to add any pop, his performance will likely be based on the guys behind him.

Made total sense at the time. Eaton is a little dude, with an extended track record of hitting groundballs. Last year, as an everyday player, Eaton was literally out-homered by Ben Revere. He went deep just the once, and so he was seemingly easy to project. Speed and contact. Decent number of walks. We all knew what Adam Eaton was, up until we didn’t. This season, Eaton’s already knocked nine dingers. Put another way, he’s tied with Adrian Beltre. Chase Headley and Jason Heyward, too. Adam Eaton wasn’t going to add any pop. Adam Eaton added a lot of pop.

The initial Adam Eaton story this year was that he got off to a dreadful start. He’s fully recovered, and that would be something on its own, but now there’s something more. As noted, Eaton has nine home runs, after having previously hit a total of six in the majors. And they haven’t necessarily come out of nowhere. I mean, when you just scan his record, they come out of nowhere, but they’re accompanied by something else. Eaton, before, has been a rather extreme groundball hitter. Eaton, at the start of this year, looked like a rather extreme groundball hitter. Here’s a graph for you.

We’re looking at Eaton’s entire career, in 30-game chunks. I didn’t choose 30 for any particular reason; it just felt good enough. There’s not really any hiding the trend. Throughout, for years, Eaton mostly kept the rolling rate at or above 50%. Only more recently has it started to drop. It’s dropped fast. Over his last 30 games, Eaton’s hit about one-in-three grounders. The Eaton we used to know came in north of one-in-two.

Grounder rate, of course, is one of those things that usually doesn’t change much unless something else has been changed. Grounders are more or less built into a hitter’s identity. The batted-ball profile comes out of the swing, affected only in small part by the opponents. As a neat little example, here’s a table, showing last years’ top 10 highest grounder rates by guys who’ve also played regularly since this year’s All-Star break. The break is an arbitrary cutoff, but it made the analysis really easy. Look at what the table tells you.

Name	2014 GB%	2015 2nd Half GB%
Ben Revere	65%	58%
Christian Yelich	61%	61%
Howie Kendrick	60%	59%
Adam Eaton	60%	31%
Jean Segura	59%	63%
Elvis Andrus	59%	48%
DJ LeMahieu	56%	58%
Adeiny Hechavarria	54%	53%
Gerardo Parra	54%	49%
Robinson Cano	53%	47%

A lot of groundballs in there. A lot of groundballs, and Adam Eaton. If you take Eaton out of it, the average of the 2014 column is 58%, and the average of the 2015 column is 55%. Just what you’d expect. Eaton, though, has turned himself upside-down. In a way that doesn’t seem explicable by randomness, Adam Eaton is hitting baseballs in the air. He’s never done this before to this extent. I haven’t come across a good explanation, but that doesn’t mean there isn’t one. Eaton might just be maturing, and realizing he has more strength than he’s been given credit for.

Which can come into play when you start getting better about reading opponents and preparing for how they’re going to attack you. Eaton doesn’t have the kind of power that’ll let him hit a home run by accident, but he might opportunistically be able to deploy a stronger swing. There has been pop in there the whole time. According to the ESPN Home Run Tracker, Eaton hit his one home run last year 111 miles per hour. That’s a real one, not a cheapie, and if a guy’s capable of that sort of homer, it suggests he could be a double-digit dinger sort.

If you examine the numbers, you see that Eaton has mostly started putting more balls in the air against right-handed pitchers. Same-handed pitchers are still keeping him on the ground. And, additionally, Eaton has done a lot of his damage against hard pitches; he’s touched them for 71% of his extra-base hits, as opposed to 56% coming into this year. What that suggests is that Eaton might be hunting for hard pitches, looking to drive them instead of slap them. He could be anticipating fastballs, and driving them better than ever before. It would be one definition of selective power.

Or Eaton could instead just be swinging harder all the time. He might have mostly abandoned the swing that would slap grounders toward third base. It’s a swing that gets programmed into every little guy with speed and bat control, but some guys like it and some guys don’t, and perhaps Eaton prefers himself as a line-drive hitter. I don’t know what might’ve prompted the change, but I don’t think Eaton’s going to complain about how things have gone.

The explanation isn’t entirely clear. The reality of what’s happening is a lot more evident. Adam Eaton, who wasn’t going to add any pop, has suddenly started driving baseballs and putting them in the air. He still can’t be described as a power hitter, but he’s a hitter with power, where he used to be a hitter with speed. The old version of Adam Eaton felt very easily predictable. We had a sense of his ability and his ceiling. Or, did we? You always have to question how much you know. It tends to be less than you think. If we misunderstood Adam Eaton’s power ceiling, almost anyone could throw us for a loop.