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To other coaches and players out there: Buy one. I cannot recommend this enough. There is almost no substitute for the advantage that this tech can create as far as pitching development goes. If you cannot afford the $4,000 price tag -- which, let’s be honest, not many high school programs can -- go find a nearby college program or a private baseball training facility that has one and see if you can use it.
That's what we did.
In March Chanhassen High School’s newly minted head coach Ross VanHauen -- a forward-thinking, Driveline podcast-listening, constant learner -- connected with Starters Sports Training in Shakopee and arranged for the program the use of Starter’s Rapsodo device at their facility as part of the pitching evaluation process. Not only would we get a consistent velocity baseline for pitchers across all grade levels, we would also be able to gather spin rates — maybe even identifying a Ryne Harper-type pitcher who may have underwhelming velo but spun breaking balls at an unhittable rate.
Plenty of the arms in the system had worked with private instructors and some had experience using Rapsodo device but for those that didn’t participate in club programs or showcase events, we wanted a better understanding of what we were working with. We wanted, nay, needed to the data.
From my personal perspective, as a new member of the Chanhassen coaching staff, these were pitchers with whom I had no prior interaction and this data could help quickly establish a roadmap going forward. In most cases, it would take days, weeks, and hours of observing bullpens and game action to properly quantify how a pitcher’s arsenal works. There are some obvious things that can be ascertained from watching a bullpen -- for instance, a pitcher’s arm slot can tell you a lot about how certain pitches should behave -- but Rapsodo data was a bridge that connected the seen and the unseen.
What the first visit amounted to was a basic light bullpen session: Each player threw 25-30 pitches, displaying their fastballs, changeups and whatever they felt was their breaking ball.
One of the initial objectives was to determine how everyone’s breaking ball works.
When you ask a young pitcher what they throw, they will often say “curveball”, a generic catchall for their secondary pitch. In actuality, it spins or moves closer to a slider or slurve. Rapsodo can differentiate this because it measures spin efficiency — basically the ratio of the transverse spin (movement spin) to total spin. Curveballs tend to have a spin efficiency over 60% (with most of the big league curveballs operating at a near 100% spin efficiency mark). What we learned on the first day with a Rapsodo was that the vast majority of pitchers in our program fell short of that rate. By our account, there were approximately four pitchers in the entire program who threw what would be truly classified as a curveball.
Here is a real world example of the difference between a high spin efficiency and a low spin efficiency breaking ball. These two right-handed pitchers in the Chanhassen program have very good secondary pitches that have distinctly different movements. On the left is junior Greg Ryun (2020) while on the right is freshman Jake Ryan (2022).
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Here is their breaking ball grips at release:
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On the left, Greg’s breaking ball had over ten inches of horizontal break and five inches of drop on average with a 49 percent spin efficiency. This running slurve aided Greg in registering 27 strikeouts in 20.1 innings in the varsity season. Comparatively, Jake, who spent his first year in the program at the junior varsity level, had a breaking ball with five inches of horizontal run and nearly 20 inches of vertical break and a robust spin efficiency of 89 percent. This big breaking 12-to-6er complemented his high spin fastball extremely well.
You can see how the two pitches fall on the pitch type spectrum.
A lot of how a pitcher’s breaking ball moves is connected with his arm slots. As pitching instructor Lantz Wheeler explains, it’s an arranged marriage: Those with a three-quarter or lower tend of have more slurve, horizontal running breaking balls while those with over-the-top deliveries favor 12-6 breaking ball action. This was a big distinction between pitchers like Greg, who released his pitch at a little over five feet in height, compared to Jake, who released his closer to six feet in height.
What can you do once with that data and knowledge?
Let’s say you are a pitcher with a low spin efficiency breaking ball, what could you do going forward? From a practical standpoint, you could do several things. You could attempt to adjust the grip and/or release to create more of a curveball action. You could embrace the slider ride, trying to reduce that spin efficiency and increase some velocity. Using Greg’s slurve as an example, if he were so inclined he could refine it into more of a slider, adding velocity and reducing the spin efficiency. It would better suit his arm angle. That said, if he wanted to have more of a curve sharp he could work on increasing the vertical drop. Or do both.
However, without regular access to a Rapsodo and having a high-speed camera fixed on the pitcher’s release point, trying to adjust is a time-consuming trial-and-error experiment.
Coach: Try to spike the seam and do this at release.
Pitcher: How’d that look?
Coach: Better...maybe? Did you keep your fingers to the side or on top?
Pitcher: I don’t know.
Coach: OK, well, try that out on the mound next game and see what happens.
That’s why professional organizations have invested heavily in that technology.
As recently as 2016, then-Minnesota Twins closer Glen Perkins talked about his process of trying to tweak his slider grip where he simply threw it a few times in the bullpen, felt like it moved better north-south, and then threw it that night in a game.
No data. No numbers. All feel.
The next offseason following Perkins’ slider tweak, journeyman reliever Craig Breslow tried to rejuvenate this career with the help of a Rapsodo device, which earned him a contract with the Minnesota Twins. That spring, the Twins bought one of their own and tried it out on their spring training backfields. Now they have them everywhere. You can choose to approach player development without that information of course, but it is an analog approach in a digital world.
In just limited exposure to the machines, the value Rapsodo data can provide in analyzing breaking ball was clear to see. In the next post, we will discuss how fastballs can be optimized under the power provided by the pitch-tracking tech.
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