Just because of the sheer number of taken pitches in a season, hitters will frequently disagree on a call with the judge standing behind them. A certain number of disagreements are to be expected, but from the sounds of things, Dexter Fowler feels like he’s been disagreeing more than usual. Fowler doesn’t think his approach is worse, but his numbers are worse, so he identifies some iffy calls as a factor. This is what Fowler looks like after an iffy strike call:

If that isn’t enough, here’s another example:

If that isn’t enough, here’s another example:

Late last week, Fowler was frustrated after a game in which he struck out looking three times. One of those came on a certain third strike, but here are the other two:

Both times, the third strike was at least questionable. Both times, it came in a full count. It’s easy to understand why Fowler would be upset, given what he and his Chicago Cubs are playing for. This also presents a good opportunity for investigation. There’s a theory, thus, that Fowler has kind of gotten screwed this year, compared to the average. Might it be true? And in the bigger picture, who has gotten screwed, and who’s hasn’t, from the hitter’s side?

It’s time to pull out a familiar tool: the difference between actual strikes and expected strikes. I usually do this when I’m looking at pitchers and catchers and whatnot, but it can also apply to hitters. Here’s an example of something I wrote on the matter a couple weeks ago. We know how many strikes there have actually been. With zone rate and out-of-zone swing rate, we can calculate an expected-strikes number. Then we just find the difference. It’s not perfect, but it is quick and easy, and it can tell us something about who has and hasn’t had a strict called strike zone.

For this year, I looked at guys who’ve faced at least 1,000 pitches. Here are a couple top-10 lists. First, the biggest positive differences between actual strikes and expected strikes. Then the reverse. The former means the hitter could be said to have gotten screwed. The latter implies the zone has been tight, and therefore hitter-friendly.

More actual strikes than expected strikes

Based on this quick glance, Pollock has had the most pitcher-friendly zone. Perhaps more notably, there’s Fowler, right there in fifth, a fraction of a strike behind Smith. So at this point, Fowler’s theory appears to be somewhat valid. We’ll come back to that. But first, the other list:

Fewer actual strikes than expected strikes

The opposite of A.J. Pollock would be Adrian Gonzalez, who’s so far seen a very friendly strike zone. There’s a lot of talent on this list, so there could be a relationship there. Perhaps it’s umpires giving certain hitters the benefit of the doubt. Perhaps it’s these players knowing which pitches are the right ones to lay off. Perhaps it’s something else, or randomness. Whatever the case, these called balls aren’t hurting. Against most of these guys, pitchers need every strike they can get.

Let’s return, somewhat, to Fowler. This season, in terms of the difference between actual strikes and expected strikes, he ranks in the sixth percentile. That’s obviously bad for him, but Fowler’s complaint is more that things have been worse for him than normal. Is it possible this is just his normal? For comparison: A season ago, Fowler ranked in the 28th percentile in the same statistic. Still not good for him, but definitely better. So by that indication, Fowler’s zone has indeed been worse.

We can take last year’s rate and apply it to this year’s numbers. As noted, Fowler right now is at +28 extra strikes. After this many pitches, by last year’s rate, he would’ve been at +9 extra strikes. That gives him a year-to-year increase of about +19 strikes. That increase ranks 10th-highest in baseball, among hitters who’ve seen at least 1,000 pitches. Didi Gregorius comes out at No. 1. He’s followed by Robinson Cano and Reynolds. These are guys whose strike zones appear to have gotten more difficult (for them).

At the other end, Markakis has the biggest drop. Then Machado, then Harper, then Adam Lind. These guys have gotten more friendly strike zones. Relative to a year ago, they’re seeing fewer called strikes, and more called balls, adjusted for changes in zone rate and so forth.

Leaving the microscope over Fowler just a little bit longer, this year, by Baseball Savant, he’s tied for second in baseball in called third strikes out of the zone. He has 19; he had 13 last year. Meanwhile, StatCorner offers some useful statistics. There’s the rate of pitches taken in the zone called balls, and there’s the rate of pitches taken out of the zone called strikes. Fowler’s changes:

Pitches taken in the zone called balls

2014: 87th percentile

87th percentile 2015: 72nd

Pitches taken out of the zone called strikes

2014: 53rd percentile

53rd percentile 2015: 16th

What the first one addresses is a drop in rate, where Fowler this year has gotten fewer called balls in the strike zone. The second one addresses a hike in rate, where Fowler this year has gotten more called strikes out of the zone. The entire landscape agrees with itself; from the indications, Dexter Fowler this year has dealt with a less-friendly strike zone than he did last year. His shift has been relatively dramatic. It’s easy enough to dismiss hitters complaining when they’re frustrated, but Fowler’s eyes haven’t lied. He’s not the only guy getting hurt, but he doesn’t need to care about the other guys.

Hitter strike zones are less of a skill than pitcher/catcher strike zones. Hitters have only a little to do with the zone that gets called, so for any number you see above, you should mentally be regressing pretty strongly toward the league average. But every call does count, and in certain cases, you can kind of understand a pattern. Fowler, for example, shares a division with the Cardinals, Pirates and Brewers, who have pretty well established pitch-framers. That’s going to have an effect, and it’s going to be frustrating. In the end, some things will even out. You’ll have to forgive Dexter Fowler and a handful of other players if they’re skeptical.