We all had a good sense going into things last season that the Tigers would have a pretty lousy team defense. The Tigers themselves understood defense wasn’t the priority, and in the end, they allowed the second-highest BABIP in the American League. Yet Max Scherzer, individually, finished at .259. At the other end of the spectrum, the Royals and Cubs featured pretty good overall team defenses. Edwin Jackson allowed a .322 BABIP. Wade Davis allowed a .361 BABIP. Defensive performance, not unlike run support, varies, and different pitchers can get different levels of support from the same group of gloves. Of course, BABIP isn’t explained by defense 100%, but it is a major component. It’s defense, pitching, and luck.

Along similar lines, just as we understand which teams do and do not have good defenses, we’re developing an understanding of which teams do and do not have good pitch-receivers behind the plate. The Braves, for example, have long had quality receivers. Ryan Doumit’s employers, meanwhile, have been a catastrophe. But pitch-receiving performance also varies, in large part just because of our small sample sizes, meaning two different guys on the same staff can end up pitching to different strike zones. So while we’ve talked about catchers here, I want to spend this post talking about pitchers. Which pitchers in 2013 threw to the biggest zones? Which pitchers threw to the smallest ones?

I’ve written posts like this before, and the numbers come out of calculations using numbers available on FanGraphs. The key number is going to be something called Diff/1000, and if you don’t remember what that is, it’s the number of extra strikes above or below average per 1,000 called pitches. “Diff” refers to it being the difference between actual strikes and expected strikes, which I figure out looking at pitches in the zone and swings at pitches out of the zone. This isn’t the most rigorous approach, but it is a simple one that gets us a lot of the way there. Think of it as OPS, where pitch-by-pitch data might be more like wOBA or wRC+. I’m okay with OPS. It usually doesn’t lie to you.

As stated before, a weird BABIP is explained by defense, pitchers, and luck. A weird Diff/1000 is also explained by defense, pitchers, and luck. A contributing factor will be the pitch-receivers. A contributing factor will be pitcher command. And then there’s the luck, or the uncertainty, or whatever you want to call it. There might be an approach here to use this data to approximate command ability, but that’s a project for a later date. For now, here’s a spreadsheet containing data for every pitcher in 2013 who threw at least 500 pitches that were taken for balls or strikes. Incidentally, when trying to understand Diff/1000, know that, on average, 1000 called pitches covers a little over 110 innings. Now let’s look at the top ten pitchers in extra strikes received:

It’s Marco Estrada in front by a billion. The gap between Estrada and second place is as big as the gap between second and 23rd place, in order to grant you a little perspective. All these pitchers threw to pretty favorable zones, but no one’s zone compared to Estrada’s in terms of generosity. You see two teammates of his also in the top ten, but behind Estrada by more than 20 strikes. So, fairly remarkable, as these things go.

Of course, Estrada, Lohse and Gallardo got to pitch to Jonathan Lucroy and Martin Maldonado, who are proven to be good receivers. For the same reason, it’s not surprising to see Hellickson’s name. Hellickson threw an awful lot to Jose Molina. Westbrook threw to a different Molina. Locke threw to Russell Martin. Robertson threw to Chris Stewart. It’s weird to see Marquis and Stults, kind of, especially given Marquis’ ugly K/BB numbers, but the Padres posted excellent framing numbers this season so some pitchers were bound to show up near the top of the list. It makes you wonder about Marquis’ command, but he also just wasn’t good. It’s conceivable that, with worse catchers, he would’ve been more not good.

With all these guys, you have to figure hitting spots played a role. They also clearly received support from talented catchers. It’s always going to be about both, so, come to terms with that. Know it, understand it, and never forget it.

At the other side, here are the bottom ten pitchers in extra strikes received:

I’ll grant it’s not the most fascinating list of names. A big part of that is because four of these names are pitchers who were on the Twins, and the Twins’ pitching staff was historically incapable of generating unironic fascination. It’s also a list with a lot of relievers, because relievers had smaller sample sizes of called pitches, and smaller sample sizes allows for greater variation. Garrett Richards is a guy who just missed this list. Jose Fernandez didn’t get receiving support. Juan Nicasio and Justin Masterson are among other starters who pitched to tinier zones.

One more time: it’s location and it’s framing. It makes absolute sense to see so many Twins, because they just didn’t have real defensive catcher alternatives to Joe Mauer. If you stop and think about it, Twins pitchers threw to a significantly smaller zone than, say, Brewers pitchers, and it’s weird that that’s a part of the game. A lot of people argue that framing isn’t a positive phenomenon, and pitchers should already get punished in other ways for lousy command. The rulebook suggests that all pitchers should pitch to the same zone, and the reality is that that doesn’t happen, and that makes things really complicated. What would these staffs look like if the zone were uniform and consistent? We can’t know, and true comparisons are difficult. But this is getting messy.

Marco Estrada pitched to the biggest zone. Josh Roenicke pitched to the smallest zone. In order to help you visualize that, here are some visuals, from Texas Leaguers:

(Estrada)

(Roenicke)

Estrada got a lot of strikes pitching down in and beyond the zone, which is Lucroy’s pitch-framing specialty. Roenicke didn’t get those strikes, nor did he get many other strikes around the edges. For the most part, Roenicke was given the rulebook strike zone, but he didn’t get those extra strikes outside of it, and within, there were a few too many balls. One notes that Estrada posted excellent strikeout and walk numbers, while Roenicke did not. Yet, for all that pitching down, Estrada also coughed up 19 dingers. One of the bewildering things is that the Brewers’ pitching staffs haven’t been better. They make one wonder about other, mostly unseen effects of throwing to a quality receiver.

A last thing for us to look at is a table of the biggest changes from 2012 to 2013. Did certain pitchers start to throw to much better or worse receivers? Did pitchers demonstrate changing levels of command? Is it mostly all just noise? On the left side, the biggest Diff/1000 improvements. On the right side, the biggest Diff/1000 declines.

The biggest improvement, far and away: Jerry Blevins. The biggest decline, far and away: the now familiar Josh Roenicke, who was actually above-average in this department the year before last. For an idea of how these things are complicated, while Roenicke’s walk rate went up, so did his strikeout rate, too. He did turn in a generally worse performance. Blevins chopped a chunk off his walks while keeping his strikeouts and limiting hits.

Arroyo fell victim to inferior framing by the Reds’ catchers, but his numbers didn’t actually suffer in any way that I can identify. Gee was fairly successful, albeit with fewer whiffs. Smith benefited from an improved receiving situation in Cleveland. Rogers was happy to throw to an improved J.P. Arencibia instead of Wilin Rosario, Lou Marson, and old Carlos Santana, but then that makes Cecil (and Loup above) confusing. Wright seemed to find new life with a catcher who could handle his sinkers. And so on, and so on. Chen didn’t get to pitch to his familiar zone. He wound up with an ERA a little over 3.

It’s hard to tell what this stuff means for individual pitchers, because we just don’t know much about other effects, aside from just straight-up extra strikes or balls. We don’t know how pitchers pitch differently with good receivers. We don’t know how pitchers pitch differently with bad receivers, trying to compensate. As a general rule, it’s better to have more extra strikes than fewer, because strikes are better than the alternative, but it’s obvious the relationship isn’t that simple, at least from this close. Beneath numbers that seem simple, there’s a world of complexity.

But the complexity helps to keep the game engaging and fresh and worth thinking about. Last year, Marco Estrada threw to a way more favorable strike zone than Josh Roenicke did. The year before, Roenicke’s zone was more favorable than average. So what? That’s exactly it. “So what?” is the very question.