As a FanGraphs reader, you’re probably familiar with Brian Bannister. The former big-league right-hander — and current director of pitching analysis and development for the Boston Red Sox — has been featured here numerous times. Bannister has previously expounded on back-up sliders, spin rate, spin axis and more. Today, the subject is changeups.

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Bannister on changeups: “The term changeup is actually somewhat deceiving. It’s traditionally been taught to be a pitch that is simply slower than your fastball. If you look at the pitchers who have the best changeups, and who have had the most success at the big-league level — the Felix Hernandezes and Zack Greinkes of the world — one, they’re hard, and two, they have a lot of movement. Pitchers who simply try to take speed off the changeup ultimtely fail with the pitch. That helps make the name a contradiction.

“The manipulation of the pitch is a very personalized process. There isn’t any right or wrong way to develop depth on a changeup. You can remove spin. You can flatten out a spin axis. You can have a lower arm slot than on your fastball. You can have a different finish, after the fact, like a Tyler Clippard. There are multiple variables you can mix in to create a deceptive pitch, and to add depth to the pitch.

“Every pitcher is going to be unique. There are multiple tools, as a pitching coach or as a pitcher, that you can adjust in order to create more depth. It’s going to be unique to the pitcher’s body type, to his athleticism, to his finger and hand size.

“There are two variables. It’s a lack of spin or it’s a flatter spin axis. Both contribute to gravity having a greater pull on the pitch, which ultimately leads to depth. It’s similar to a two-seam [fastball] that way. When you can reduce the amount of backspin on the ball, you’re reducing its perceived rise.

“Pedro Martinez used to squeeze his index finger really hard, because it naturally curls the other fingers. When the fingers are shorter, it creates less spin. That helps create more depth, because with less spin, gravity pulls on the ball more. Tom Glavine used to take his index finger and squeeze the outside of his thumb, which did the same thing. It tightened up his fingers, so he was able to spin the ball less.

“When you see Greinke or Clippard… even Pedro used to do it. He’d finish on the first-base side of the mound on his fastball. He’d finish on the third-base side on his changeup. A hitter doesn’t have time, once the ball is released, to see what side of the mound the pitcher is going to finish on. What he was doing was adding more depth to his changeup when he did that.

“With splitters, you’re reducing spin, but I think the good ones also have more of a horizontal element. They have more of a tail. Whether that’s hooking a seam with your index finger… look at Koji Uehara, for example. He’s got excellent horizontal movement on the pitch. It’s beneficial to have that as well as vertical depth.”

“There are just so many ways to go about it. That’s why it’s such a fun pitch. There are so many elements you can play with, and there’s not one right or wrong. You’re just trying to get to a productive final result.”