The Latest Stage of Bryce Harper’s Development

Bryce Harper went and had himself a game Wednesday afternoon, and now, we can say these things, and not be lying: Harper is sitting on a career-high wRC+. He’s sitting on a career-high isolated power, and a career-high walk rate. Harper, by the way, is still 22 years old. It’s always mandatory to put that in somewhere. It’s a pretty big part of the picture.

It makes sense, then, to talk about what’s going on with Harper’s development. The world’s been waiting to see if he can ever try to catch up to Mike Trout. Ben Lindbergh has written about what seems to be a gain regarding Harper’s eye. Harper, also, has worked to calm down his swing a little bit, at the suggestion of his hitting coach and his manager. Back in April, Matt Williams said this:

Williams said the single to left was a particularly important example of what Harper needs to do to be successful and hit for a high average.

Williams liked to see Harper shooting balls the other way. Harper has long been personally obsessed with shooting balls the other way. Wednesday, the first of Harper’s three homers was slugged the other way. What you’d think is, maybe, Harper’s getting even better at using all fields. Truth be told, at least to this point, Harper’s gotten better at using just one of the fields.

Pulling from the spray charts on his player page, here are Bryce Harper’s balls hit in the air, from his first three seasons. I’ve added a thin gray line, splitting the field in halves. There’s the pull side, and the other side. Ordinarily, the field gets split into thirds, but why not make things 33% simpler?

That image doesn’t do a lot of good on its own. You do, at least, see balls hit everywhere. Pulled homers, homers up the middle, and homers the other way. But the image is more useful when it can be compared with another. Now Harper’s balls hit in the air, for just 2015. Because I’m writing this before the spray charts update, I’ve added three black dots to capture Wednesday’s homers. I guessed at their locations, but there’s no question which half they were hit to.

Suddenly, the other half looks somewhat empty. We can bring this together and apply some numbers. In the following graph, you’ll see a rate for all balls in play, and a rate for just air balls.

Used to be, Harper pulled 55% of his balls in play, and 43% of his balls in the air. Though it’s early in this season, the numbers to this point are 73% and 72%, respectively. Interestingly, he’s pulling more air balls while not really pulling more groundballs. Seems to me that’s a good thing. Pull more grounders, and you make yourself more shiftable. Pulled air balls, though, tend to be the more dangerous ones. Harper can sting the ball anywhere, but he’s going to be his strongest to right and right-center.

Harper is hitting more dangerous air balls, and he’s hitting more air balls. Incidentally, it’s not unlike the transition Trout began last season. It’s somewhat implied that Harper is hunting, and he’s not ending up behind on pitches or mis-hitting them. That might indicate something about his eye. The swing rates definitely suggest that Harper is being a little more patient than he’s ever been. His zone rate, meanwhile, suggests pitchers don’t want to play with him too much. Harper has swung at fewer balls and fewer strikes.

But it’s not like he’s necessarily flipped a switch. A good measure of aggressiveness is first-pitch swing rate. His first three years, Harper swung at about two-fifths of all first pitches. So far this year, he’s swung at about two-fifths of all first pitches. So Harper’s still willing to take a rip. He’s just a bit more selective, and the other numbers say he’s seeing the ball better and making stronger contact.

I think I’ve mentioned before that I’m not a swing analyst. But at this point, the swing has to be considered. Harper’s worked on it a little bit, and while you can’t reach sweeping conclusions based on single-swing samples, there are little things you can note. Let’s watch some Harper dingers, from each of the past three seasons:

2013

2014

2015

People love to talk about his back foot lifting off the ground. F.P. Santangelo brought it up on the Nationals’ broadcast on Wednesday. The foot’s always come up, and the foot’s always going to go up. But look at the foot right before it goes up. In the 2013 swing, it just leaves the ground. In the 2014 swing, it’s basically the same. In the swing from Wednesday, there’s a little toe grind and a push. Which suggests more weight on the back leg, which implies Harper stays back longer before completing his weight transfer. And the transfer obviously completes, with the back foot lifting and the front leg straightening.

You also get the sense Harper has a broader base, and he seems to be lower and less upright at contact. It follows he’s getting a little more strength out of his legs. Which means he needs less from his upper body. There are elements of improved control within what’s been one of the most violent swings in the game.

What might explain Harper being more disciplined? It could, firstly, be a conscious thing. Then there’s the matter of his staying back more — that could buy him precious milliseconds, before he commits. And there’s his head movement. This is from 2013:

Nationals officials say he actually was swinging harder when they drafted him — so hard, Schu said, his head would move as much as two feet during a swing. The “head travel” prevented Harper from recognizing pitches and led to misses. Schu expressed the need for Harper to stay within himself and keep his head still.

I don’t know if Harper’s head is moving less than it used to, in the majors. But if his swing is more controlled, it makes sense that his head might be more controlled. It’s important to understand that discipline is influenced by multiple variables. There is, of course, just a guy’s regular pitch recognition, but there are also mechanical elements. One guy might transfer his weight too early. Another guy might move his head too much, or spend too little time with two eyes on the baseball. It’s easier to recognize something you can see clearly, without your head bobbing around.

For Bryce Harper, there’s a lot that could be going on. Some of this has been speculative, and there’s a difference between speculation and fact. But, what we know: Harper’s driving more balls to right field. He’s putting more balls in the air. And he seems to be more disciplined than before, having made some tweaks for just that purpose. The speculation has tried to explain the facts of the case, and it’s the facts of the case that should be so terrifying for rival pitchers. Bryce Harper, see, appears to be getting better. Being a batter is about seeing the ball and hitting the ball. There are indications Harper’s getting better at both.