Matt Garza Understands His Catchers

One of the things you’re supposed to learn about in a literature class is subtext. Subtext isn’t exactly a “hidden meaning,” but it’s the unspoken thematic uncurrent of a particular narrative or conversation. While the following will appear to be another post in a long line of posts about Jonathan Lucroy’s pitch framing (It is!), there’s a broader subtext driving the conversation as well that we’ll discuss at the conclusion.

The essence of pitch framing is well-established and relatively simple. Due to the imperfect nature of human eyes and the lack of a uniformly enforced strike zone, the way a catcher receives a pitch can influence whether that pitch is called a strike. Certain catchers have the ability to make balls look like strikes and to make sure that very few strikes look like balls. And certain catchers obviously lack this ability.

The way a catcher receives the ball influences the call, meaning good framers reduce the number of runs scored against their team and make their pitchers look great in the process. Jonathan Lucroy, catcher extraordinaire, is someone who seems to do this very well.

The two leading framing metrics (via Stat Corner and Baseball Prospectus) mark Lucroy among the best in the business:

Year	Innings	StatCorner RAA	BP RAA
2010	655	23.6	25.1
2011	1,043.2	41.9	38.8
2012	717.1	22.9	21.2
2013	1,074	29.7	28.5
2014	1,182.1	22.1	12.3

And while framing metrics are relatively new and aren’t always taken completely at face value, consistent readings like this suggest that Lucroy is probably quite good. And while the metrics are feeding the reputation, Lucroy also has a public reputation as an excellent framer. Players and coaches who don’t spend much time reading sabermetric blogs also consider Lucroy to have a talent for stealing strikes, and the numbers agree. Both of those facets are important.

Turn around and look at someone like Welington Castillo, the recently displaced Cubs backstop. His framing numbers and reputation are, let’s say, worse:

Year	Innings	StatCorner RAA	BP RAA
2010	44	-3.1	-1.5
2011	31.2	-1.7	-1.4
2012	413.2	-5.4	-3.7
2013	956	-16.7	-16.5
2014	916.1	-24.3	-12

No one is going to challenge me if I argue Lucroy is a better pitch framer than Castillo. Plenty of people will wonder if the difference between the two is really three or four wins per season, but it would be tough to locate someone who thinks Castillo is significantly better than Lucroy at receiving the baseball.

This comparison opens the door for an interesting case study, the first bit of which is an obvious and well-flattened path. When a pitcher leaves a bad framer for a good one, what happens? Obviously, the pitcher gets a higher number of called strikes, controlling for any intervening variables. That’s basically tautological. Matt Garza made this transfer in 2014 and the universe followed the rules, however subtly:

Year	Called Strike% (In Zone)	Called Strike% (Out of Zone)
2013	91%	16%
2014	91%	18%

But there’s another wrinkle in this entire enterprise that doesn’t get enough attention, mostly because it’s complicating an already complicated measurement strategy.

Imagine that you could play two concurrent baseball games that were identical in every way except for the catcher. If the catchers were Lucroy and Castillo, you would expect the Lucroy game to include a higher number of called strikes because a small number of borderline calls would likely go his way. That’s framing!

But if we take the experimental restraints off the pitchers and let this scenario evolve like it would in the real world, Lucroy wouldn’t just get better calls on the same pitches, he would guide his pitcher to throw pitches farther and farther away from the center of the strike zone, even if he’s essentially calling the same pitches. Call it “second-order framing.”

The pitcher, at some point in time, develops an opinion about his catcher’s ability to frame pitches (his reputation) and also observes the actual, tangible results (his statistics). If you’re throwing to someone you think is a bad framer, you would presumably throw the ball closer to the zone than if you were throwing to someone you think is an excellent framer. Now of course, no pitcher has the kind of pinpoint control to consistently hit their target on the nose, but on average, a pitcher who is throwing the ball three inches outside will throw the ball farther outside than someone aiming one inch outside.

In other words, Garza moving from a very bad receiver (Castillo and others) to a great receiver (Lucroy) should not only lead him to a higher called-strike percentage, it should lead him to a zone profile with more focus on pitches below the zone and beyond the corners. If Lucroy is as much of an upgrade as we think he is over Castillo, it should lead Garza to change the way he populated the strike zone in 2014 compared to 2013 because he knows he’s working with a bigger zone:

Year	“Low Pitches”	Below 10″	10″-14″	14″-18″	18″-22″	22″-26″
2013	917	16.91%	9.76%	14.98%	23.72%	34.62%
2014	813	18.94%	12.67%	16.48%	24.85%	27.06%

Hey look, it does! This chart reflects all pitches thrown by Garza that were:

• Within six inches of each corner (horizontally).
• Fewer than 26 inches off the ground.

If you divide the normal strike zone into thirds, this is the bottom third of the zone and everything below it, extended six inches horizontally in each direction.

The 2013 data is every pitch Garza threw that was recorded by PITCHf/x, via Baseball-Savant. The 2014 data is every pitch Garza threw to Lucroy that was recorded by PITCHf/x, via Baseball-Savant. Of the pitches we would say are close enough to the plate to be contested, these are Garza’s “low pitches.” And when he threw low in 2014, he threw lower than he did in 2013, particularly in the two tiers right below the 18-inch mark, which is the approximate bottom of the zone.

Obviously we can’t be perfectly certain about the causes driving this because Garza’s talent level could have changed, the ballpark, hitters or circumstances could have been arranged differently enough to lead to a different approach. There are also various measurement issues (and some missing data) that pop up anytime you’re dealing with PITCHf/x data that’s measured in fractions of an inch. We also know the strike zone grew in 2014. Still, it didn’t drop to this degree.

Which means framing is probably even more nuanced than we usually acknowledge. Not only will the same pitches get called differently with two different catchers, but pitchers will further expand the zone as a result of their opinion about the difference between catchers. This isn’t a shocking or surprising belief, but it’s an important one to consider when people debate the relative size of framing effects.

Not only does Lucroy get better calls on the same pitches, but that fact creates more pitches in the areas around the plate in which a pitch can be framed. And those pitches are also usually more difficult to hit, which is another point in favor of the great framers.

It’s always tricky to analyze anything that rests on determining where a pitcher meant to spot the baseball, and this is just a single example. But the idea makes sense and we can observe it happening in the cleanest possible case study (Castillo and Lucroy). There are many complicating factors, but this is something that might help us come to terms with the magnitude of the framing numbers.

It might not seem like Lucroy should be able to find a couple of wins per season above average by stealing extra strikes, but if great framers are also creating more opportunities for themselves — and poor framers are creating fewer (a good area for future study) — it all starts to look a little more plausible.

The bottom line is this indicates pitchers have tons of confidence in Lucroy and in framing numbers, but what’s hiding behind that is the idea that good framers don’t just steal strikes — they keep the ball away from the heart of the plate simply with their presence.