As I dive deeper into data, the one thing I become more convinced of is that consistency is the most important thing for a pitcher. If you can get your delivery to be consistent, you’re going to be able to reliable put the ball where you want to. The most important thing in pitching is throwing strikes, and consistency makes that easier.

So, Sean and I had a bullpen with one of our guys this week. I got PitchLogic data on his pitches and I pushed it into the Python visualization code I’ve been working on. Among the charts it creates is one for movement by pitch type. On that chart, it creates a box that’s where about half the pitches would be if he threw with this consistency. So, for some players and some pitch types, it can be very large and for others, very small.

For these four-seam fastballs, that box is about 4 square inches. You can see most of his pitches are near it and a third of them are in it.

If Player One can get all of his four-seam fastballs to move 15 to 17.5 inches vertically and around 8 to 9 inches horizontally, he’s going to be consistently hitting his aim point.

Our goal isn’t for all of our pitches to put their pitches in his box, but, rather, that he consistently throws his four-seams this way. If he does, he can change his aim point and dominate hitters.

Every player is going to have a different box. Here’s a younger player whose box is about 10 square inches. As he gets more consistent, there will be fewer outliers and his box will get smaller (and he’ll throw more strikes).

I’ve only recently come up with this box – so recent that I don’t even have a name for it. It’s from the inter-quartile range of the movement data, so I could call it the IQR box, but that would get everyone asking why it’s called that instead of what it means and how it’s used. Maybe I could call it the MCB – Movement Consistency Box?

The PitchLogic ball auto-tags the pitches by type. I love this because it points out when players are not doing what they intend (throwing a cutter when they want to throw a fastball) or when they are mislabeling their pitches (throwing a cutter but calling it a fastball). The unintended variety tend to be younger players, while the mislabeling tends to come from high school players.

For our bullpen the other night, four pitches go auto-tagged as cutters. All four would have been down and to the left of the MCB for his four-seam fastballs. So, these wouldn’t have gone where he thought they would go. He also lost velocity on each of them. So, that high, hard inside pitch ends up slightly slower and out over the plate. Yikes!

Is it due to incorrect grip? Or a bad release? Is it lack of pronation? I honestly don’t know, but I know it’s something we’ll investigate and work on. I also need to check location on these pitches – time to get back to the code!

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I’m not including any of the visualization posts in the Coaching Courses because they don’t really fit. They’re a bit esoteric and not really what you need to start coaching. It’s fascinating stuff, though.