Salvador Perez's plate discipline might actually be getting better

Is it fair to say that Salvador Perez is an important part of the team? That's more than fair. He's signed for a long time and appears to be the heart, soul, and wit of the team. He can just as easily fool around with Lorenzo Cain on Instagram as throw out a runner trying to swipe a base (any of them) or even get back to their original base (any of them).

We know he has good defensive qualities. He also has good power. What some of us might know the most is his utter lack of plate discipline. His walk rate of 2.4 percent last year was all kinds of bad. Plate discipline with Perez is often top of mind here.

Here's Matthew LaMar back in February:

I love Salvador Perez. But I prefer the precise, patient Perez of 2012 over the one who swung at four balls above his shoulders against Madison Bumgarner in Game Seven in 2014

Here's Shaun Newkirk in September of 2014:

Now maybe Perez does in fact carry his poor 2nd half into next year and beyond. That would be an utter collapse, but a return to his career walk/swing rates, and BABIP should return him to around the same level of player we've grown to love out of Perez

Here I am back in July of 2015:

Honestly, if there is a relationship here between his declining grounder production and better fly ball production due to elevating inside pitches more, I'll take the fly balls over the grounders.

If only he could fix that walk rate.

It's quite clear that we care a lot about Perez's plate discipline. Royals Review has looked at Perez's plate discipline multiple times over his career. Connor Moylan had a two-part series three years ago. Connor concluded that Perez's hot spot, middle inside, was not where the majority of his swings were.

Connor's prescription:

First of all, I think Perez should be more aggressive early in the count; Perez hardly ever swings at the first pitch, regardless of location. Second, I think Perez has issues recognizing sliders, specifically from right-handed starters.

Jeff Zimmermann looked at Perez several times back in 2012. Here's March, July, and September.

His plate discipline was a concern at the beginning of his career, and it's still a concern now. Certainly the team realizes it. Perez himself realizes it. Here's the big man himself talking about his plate discipline woes in an article by Jeffrey Flanagan:

"That's the one thing I want to do -- be more patient and see more pitches," Perez said. "I know I can get better pitches to hit if I'm more patient. It's hard, but I have to do it."

I wish I could tell you exactly when that article was written, but the article does not have a timestamp anywhere I could see. I'm pretty sure it was late March, as it was featured in a Royals Rumblings column around that time.

So...what's Perez done so far in 2016 about this issue? It seems there's at least a little positive movement, but it's still early. Keep that in mind.

As of this writing, Perez's walk rate sat at 4.3 percent. 4.4 percent is the best single-season walk rate of his career, so there's that. As far as more underlying data, the trends are mostly good. Both variants of plate discipline data on FanGraphs show a decrease in the rate at which Perez swings at pitches outside the strike zone. However, those numbers also show a decreased contact rate, which helps explain his high strikeout rate.

This phenomenon is a little interesting, a double-edged sword if you will. If Perez is whiffing on pitches outside the strike zone more, then in many cases he has the opportunity to swing at a better pitch or take more pitches for walks. On the other hand, he'll also strike out more.

Important and related to the plate discipline numbers is the location of pitches at which Perez has swung. The following two heat maps from Baseball Savant compare 2015 swings vs. 2016 swings (from catcher's perspective).

2015

2016

Small sample size and such, but there are some good things going on here. First, there's that dark red spot in the middle-in ish portion of the plate. Many of his swings are in a part of the plate where Perez can do some damage. Also notice that although there is a sizable portion of pitches outside at which he has swung, there's a gap in the low and away off the plate portion. Those are pitches with which Perez does little.

The swing selection has led to a drastic change in his batted ball profile, the gist of which is that Perez is hitting a ton more fly balls and elevating the ball more in general. Some of those fly balls have gone for dingers. Dingers are good. Grounders are bad.

There's still time for variation to suss out what's real and what isn't. Either Perez returns to his normal, hyper-aggressive self and doesn't walk, or he maintains some semblance of this improvement in plate discipline but continues to whiff.

Is that a worthy tradeoff? The early results say yes.