Visualizing the Pete Fairbanks slider transformation

Earlier in the day, Brian Menendez wrote an excellent article about how Peter Fairbanks has transformed his hard slider, giving up a little bit of velocity in exchange for more downward movement.

In addition to tables, annotated pictures, videos, mechanical analysis, and a lot more good stuff, this is what Brian had to say about the new slider pitch shape :

So his fastball is a little straighter, but the headliner here is that Fairbanks has added about 6 inches of drop to his slider. Additionally, it’s about 3 ticks slower, down to 87.1 MPH from 89.9. Not only has he added separation with movement, but separation in velocity as well.

Let’s remember that the 2019 version of Fairbanks’ slider was already a plus pitch — thrown hard with good vertical drop. The 2020 version retains these attributes; however the relatively slower velocity and the added vertical drop compared to average sliders in its class, make it seem to pair better with his fastball.

I’ve been working on a pitch shape visualization tool that’s not quite ready for prime time, but this seemed like a good time to break it out for a teaser to show exactly the shift Brian is talking about. Note that I’m using Pitch Info numbers (what you see on Brooks Baseball), which are slightly different than the Baseball Savant numbers (what Brian used) based on their calculation method and pitch classifications, but that look very different because they’re expressed in terms of break compared to a theoretical spinless pitch, rather than as total break.

Click here if you want to play with the beta version of the interactive tool that generated these pictures.

First let’s talk about the general shape of sliders. Here’s the movement and velocity of all pitchers who threw a slider in 2020. The x and why axes are pitch movement due to spin, and the color is pitch speed, relative to average slider speed.

Please ignore the red mark in the top right and the blue mark in the bottom left. Those are “Maximum” and “Minimum” pitchers, used to set the color scale.

Pitch Info numbers from FanGraphs, Ian Malinowski viz

As you can see, pitchers are making a tradeoff between movement and speed. The hard sliders are clustered around the upper middle, while the softer sliders get more drop and/or sweep. I like to think of slider quality as being somewhere on the edge of the three-dimensional curve of speed and movement — if you’re throwing hard for the type of movement you’re getting, then your slider is probably going to work.

Below is the same graph, but with Fairbanks highlighted.

Pitch Info numbers from FanGraphs, Ian Malinowski viz

As you can see, there are plenty of sliders in the league with the same approximate movement as Fairbanks. He sits in a clump of right-handed pitchers with 2-4 inches of sweep and 0-2 inches of drop. Sliders with this type of movement at 90 mph are vanishingly rare, though.

If you look back at the unhighlighted chart above, you’ll see that the truly hard sliders are clustered in the 1-4 inches of rise section of the graph. In fact, only one other pitcher in 2019, Emmanuel Clase, achieved downward magnus force (y<0) on his slider with an average speed over 90 mph.

But as Brian discussed, Fairbanks has given up throwing his slider in the low-90s (now averaging 87.8 mph), and in exchange has achieved more downward movement (-3.8 inches) . Here are the pitchers who have thrown sliders in 2019, with Fairbanks highlighted.

Pitch Info numbers from FanGraphs, Ian Malinowski viz

And here’s both 2019 and 2020, to emphasize the difference.

Pitch Info numbers from FanGraphs, Ian Malinowski viz

At this point, Fairbanks has moved into the territory of exceptional slider movement, regardless of speed. There’s just not a lot of pitchers generating ~4 inches of drop period, and none of them are doing so while throwing quite as hard as Fairbanks does.

I’d say that the handful of comparable sliders in the league belong to Garret Richards, Blake Treinen, Drew Rasmussen, Tanner Rainey, Luke Jackson, and Julian Merryweather (remember this last name, Rays fans — we’re going to dislike facing him for a long time). There are a handful of comparable pitches being classified as curves (like Jose Alvarado’s), but that’s beyond the scope of this teaser article, and a can of worms for another time.

I’ll leave you with a graph of all the Rays sliders, with a haphazard, incomplete set of labels. if you want to more fully explore these pitches or others, click over to the Tableau tool, but remember this is a work in progress, and functionality may shift or cease.

First here’s 2019:

Pitch Info numbers from FanGraphs, Ian Malinowski viz

Some notes:

• The unlabeled slider on the diagonal between Fairbanks and Andrew Kittredge is Ian Gibaut, a pitcher who often gets compared to Fairbanks because of their trade and roster spot entanglement. Note that at 87.8 mph (as compared to 90.0 mph), this is not the same pitch.
• Yes, Chaz Roe is the pitcher who sets the “maximum” run for MLB (the max velo is being set by some fastballs that I somehow mislabeled — I did say this was in beta — and should probably be set by Framber Valdez, at 93.4 mph; but it’s tricky at this point because now we’re getting into cutters).

And here’s 2020:

Pitch Info numbers from FanGraphs, Ian Malinowski viz

Some notes:

• I love Ryan Yarbrough’s big, sweeping, super slow slider. I had no idea that Gilmartin threw basically the same pitch, but 8 mph faster. Interesting pitch, interesting case.
• Comparing the 2019 and 2020 slider shape for Andew Kittredge, it looks like he may have pulled a mini-Fairbanks, and gotten a bit more depth as well on his hard slider. His injury is a real shame. I’d have liked to see what he could do given the chance 2020 was set to provide him.