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Art Class: The Beauty (and Utility) of Framing

The newest discoveries in sabermetrics show that catchers have a much greater impact on the strike zone than we ever thought before.


I often recommend reading other articles in my articles, but if you're going to read just one of them, go read Jack Moore's "The Secret History of Sabermetics". Do it. Now.

Moore does an incredible job of laying out the history and the breakthroughs of the last 50 years, from Bill James to Voros McCracken to Baseball Prospectus. It's also especially pertinent to note that the article describes the amateur sabermetrics community as the forefront of new research. That's US, guys! But the article also makes mention of the newest field of research, one that's just beginning to get recognition around the internets and the league. And if you read the title of this article, you already know what I'm talking about: pitch framing.

We've known for a long time that catchers try to make bad pitches look like strikes, but we're only just beginning to discover that some of them succeed better than we ever thought. We live in an amazing age for baseball analytics: we have Pitch f/x. Pitch f/x can tell us exactly whether a pitch out of the zone was called a strike, or vice versa.

What's cool about that is we can now tell more accurately than ever before whether a team (or a specific catcher) is getting their pitchers extra strike calls, or losing them strike calls. This might not seem like a huge deal, a few strikes here or there. But those extra strikes (or balls) on close pitches can put runners on (or get runners out) that another catcher might not, and might set up those batters for better (or worse) counts.

But why listen to my words when I can show you pretty pictures? (Note- I'm horrible at making gifs. These gifs are from Baseball Prospectus' weekly wrapups of pitch framing)

Here's a great example from the God of Pitch Framing, Jose Molina, turning what should be a ball into a called strike.


As you can see, the pitch is pretty low, but Jose Molina brings it smoothly back up into the strike zone. It was called a strike. Instead of facing a 2-0 count, the batter has now got a 1-1 count, which drastically changes the at-bat. The pitch is a pretty obvious ball.

Yes, this affects the A's too. Here's Chris Stewart doing the same thing against Jed Lowrie:


On the flip side, catchers can do the opposite for you. Chris Sale throws it straight across the plate, but the catcher sure made it look like a ball.

But we knew all this already. Some of this might just be umpires expanding their zones. And anyway, how much is a strike or ball here or there going to affect you over the course of the season?

The answer is: a freaking lot. Mike Fast at Baseball Prospectus published a truly groundbreaking article 2 years ago laying out just how much a catcher can affect their team's run prevention. He noted that switching a ball to a strike call was worth about 0.13 runs, and so was able to calculate just how many runs a catcher prevents over the course of the season. The numbers are striking (these numbers are from his 2011 study):



Total Runs







Jose Molina









Russell Martin









Yorvit Torrealba









Jonathan Lucroy









Yadier Molina









That's insane. Jose Molina saves his team over 35 runs per season. That's a few wins over the course of a season. These numbers are freaking staggering. In certain parts of the sabermetric community, Jose Molina (and, increasingly, Jonathan Lucroy) are celebrities because of their astounding ability to get their pitchers more strikes and save runs. The flip side are people like Ryan Doumit, who actually costs his team over 25 runs a year based on his penchant for getting strikes called balls. It's also interesting to note that the Pirates' pitching resurgence coincided with the signing of Russell Martin. Just a thought.

On a team level, this is actually pretty easy to measure because we have such ready access to Pitch f/x stats.The way to calculate this is simple. First, you find out the rate of pitches that were officially called strikes and balls. Then, you look at the Pitch f/x data. Pitch f/x doesn't care what the umpire said- it only cares where the ball went. There are three stats that are important to us: Zone% (percentage of pitches that were in the strike zone, which are by definition strikes), O-Zone% (percentage of pitches outside the zone, which is just 1 - Zone%) and O-swing% (the percentage of pitches outside the strike zone that batters swung at, which are also by definition strikes). So our formula becomes:

Zone% + (O-Zone%*O-Swing%)

Then, you subtract the Pitch f/x strike percentage from the actual called strike percentage and you see how good the team is overall. LET'S DO IT!

The A's have thrown 14084 pitches this season, and 9179 have been called strikes, good for a 65.2% strike rate.

According to pitch f/x, the A's have thrown 50.6% of their pitches in the zone, which means they've thrown 49.6% of their pitches out of the zone. Of those pitches out of the zone, batters swung at 30.5% of those pitches. So their overall strike rate would be 50.6% + (49.6%*30.5%) = 65.7%.

So by Pitch f/x, the A's true strike percentage is slightly higher than the actual calls they've gotten by 0.5%. Jeff Sullivan at Fangraphs developed a stat called Diff/1000, which attempts to create a rate measurement how many strikes a team gets called in their favor. According to this, the A's get 0.5% fewer strike calls than they should, meaning about 1 pitch every 200 at bats, or 5 pitches every 1000 at bats.

There's obvious a lot of noise here, because not all variation in strike calls is due to catchers. A lot of it has to do with umpires, and even a few bad calls in one game can effect the stats drastically. Basically, I would conclude that the A's catchers, on average, give us a net of no gain or loss in either direction. They might gain us a call or lose us a call here or there, but on average we're getting about the same number of calls as we should be according to Pitch f/x.

A lot of pitch framing is just about the catcher being able to hold the target and remain still after the catch. A lot of that is skill and might not be teachable.However, there are some other things that have been shown to help manage the count that might be helpful.

1. Withdrawn Bunts are Often Called Balls

On Monday night, Chris Young faked a bunt attempt in the 9th inning, and the pitch looked an awful lot like a strike, but was called a ball. I don't have, so I can't gif the pitch. Pitch f/x is here, and it's less down the middle than I thought it was, but still definitely a strike.

An even better example is this pitch from Bud Norris:


The pitch is basically right down the middle, but the distraction of the bunt (and the throw to first, which we'll get to in a minute) throws the umpire off. It's hard to see as an umpire, and they rely a lot more on things like the catcher's reaction than we care to admit, and the movement of the batter throws things off even more.

I'd be interested to see some A's hitters, if they're already intent on taking the first pitch regardless, maybe faking a bunt more often and getting a borderline call to go their way.

2. If the Catcher Throws, or Fakes a Throw, It's Almost Always a Ball

As noted above, there's a lot for an umpire to look for in a strike call, and if the catcher moves quickly, it makes it very difficult for the umpire to see. When you look at the pitches that were closest to the center of the strike zone that were called balls, it's often because the catcher is making a snap throw.

Here's a great example:


The pitch is a perfect strike right at the knees, but because Stewart needs to already be in his throwing motion to nab the runner, he costs the team a strike.

On defense, unless you can be relatively certain of getting the runner, a snap throw to first (or even worse, a fake throw) is almost never a good idea if the pitch is a strike. Throwing to second in a two-strike count, even with the runner going, might not always be a great idea either if the pitch looks like a strike.

Regardless, pitch framing is one of those undervalued commodities that I'd be interested in seeing the A's try to exploit just a little bit more.