If there was a noteworthy finding in the early stages, it was that pitchers who succeed at coaxing ground balls with their changeups generally looked dissimilar from those who missed bats with theirs. The pitchers who can do both are the best. Stephen Strasburg topped that list, so the first waft of the sniff test was passed.
The difference between a bat-misser and a worm-killer mostly boils down to firmness, for lack of a better term. Having some sink (pfx_z for you PITCHf/x folks) and tilt (the vertical angle of the ball as it crosses home plate) benefits pitchers near either pole of the changeup sphere. But it diverges from there.
A fastball with plus velocity and a sizable gap (10+ MPH) between the heater and the changeup make for more missed bats with the offs-/peed pitch, while a smaller gap helps the pitcher to induce more ground balls. Everyone needs tilt and/or sink, but guys who throw hard and can get separation on their fastball/changeup combo can try to miss bats. Those who don't have that gap and/or plus velocity are generally better suited to pitching to contact.
At least, that's what the numbers say about major-league pitchers. The guys who can miss bats know it, and use their changeup to put guys away in two-strike counts. The guys who can't miss bats also know it, and try to use their changeups earlier in the count. There is also a group that does neither; however, as shown in part one, those guys are self-aware and seem to avoid the pitch in general.
Does any of this mean anything in terms of player development?
I tend to blather about the benefits of digital tracking (PITCHf/x, et al.) to player development. It's very abstract, often forced upon—I mean offered to—folks who work in baseball operations. Usually, something about modeling is thrown in, but that’s where the conversation tends to go off on tangents.
What goes into the model? Here, you end up going away from analytics—rightfully so—and right into actual baseball theory.
My study of changeups was inspired by one such tangent. At the 2013 Saberseminar, I was able to bring this topic full circle, thanks to an impressive and intimidating audience and some fellow speakers.
When I explained my findings, already discussed in the first two parts, I referred to a quartet of examples: the aforementioned Strasburg (thrower of the ultimate dual-threat changeup), Brandon McCarthy (eternally seeking an effective off-speed pitch), Jon Lester (also a dual-threat changeup thrower), and Chris Archer (developing his changeup on the front-end of his big-league career).
Take a look at the last couple of slides from my presentation. Doesn't it look like Archer belongs in the whiff-inducer group?
Archer fits the bill. Big fastball, sizable velocity separation from the changeup. It's worth noting that he's not throwing the pitch in swinging counts. As Archer discussed with Mike Ferrin on Power Alley, most days he is simply trying to get repetitions on the mound. If he can drop it in for a strike early in the count, that's great. On days he feels better with the pitch, he will try to miss bats in swinging counts.
McCarthy is the other end of the spectrum. A veteran who doesn't have the plus fastball of the live-armed Archer. McCarthy's journey toward a satisfactory changeup is well documented on Twitter. This year alone he's used three versions of a changeup. As you can see in McCarthy's scatter plot in my Saberseminar talk (linked above), he's seeking fade, depth and missed bats.
McCarthy's latest changeup was the slowest, so maybe he can go after that big speed gap and get swinging strikes that way. If not, he may be better off with a firmer variety. That happens to be exactly what Brian Bannister did.
Bannister spoke at Saberseminar, covering his full career arc. But the emphasis of his talk was finding ways to use sabermetrics to improve your own chances of succeeding as a marginal big-league pitcher. He was frank about his struggles during his talk and willing to dig deep into his thoughts on pitch development later that day.
I was lucky enough to catch him during a quiet moment, and he was gracious enough to let me ruin it.
I learned a lot during that conversation, which grew to include other conference attendees and lasted what I think was the better part of an hour. Here's an attempt to summarize, and be warned, I was not taking notes.
My basic finding about changeups rang true for Bannister. Ramon Ramirez taught him a “slip pitch” grip for a circle-change (no seams touched) and told him to throw it as hard as he could. Bannister approached it like a sinker, made a small adjustment in how he released it, and managed to turn it into a ground-ball getter.
As Bannister noted in his talk, and from the audience during an earlier talk by Dr. Glenn Fleisig, it took biomechanical analysis to show him that the “throw the changeup slow” approach he used earlier in his career was problematic. His arm was noticeably slowing down. The instructions that were geared toward taking something off the pitch and finding that big speed gap were translating into a bad habit.
Bannister recognized this point both in our conversation and in his presentation: How do you get what seems to run counter to conventional wisdom into the hands of young pitchers? What if an organization can find the “throw your changeup harder” candidates and effectively and consistently train them to do so? It may not be the path to missing bats in the minors, but for some pitchers (like Bannister), missing bats in the minors did not translate to doing so in the majors.
Now, we have a concrete and attackable problem space. Statistical and anecdotal evidence suggests that some pitchers will find more success by abandoning what may be the conventional profile for a changeup. Organizations always want more return on their player investments by turning more guys into effective big leaguers that would otherwise be churned out of the system. You can never have enough pitching.
Certainly, more analysis is required, but it seems possible to identify or qualify candidates for a firm changeup. Further qualification and/or initial identification would involve scouting and player development—who has a skill set that projects toward the MLB comps, who has the makeup to handle the change, and so on. If Bannister's experience is any guide, this could cut against the grain but also yield considerable gain.