From SABR member Eno Sarris at The Athletic on August 13, 2019:
Sliders are like fingerprints — every pitcher has their own. The most often thrown non-fastball is also the pitch that varies the most from pitcher to pitcher. Just look around the league and you’ll see Corey Kluber’s sweeper, Justin Verlander’s sizzler, Patrick Corbin’s slow bullet and Sonny Gray’s power curve. Seems impossible to describe the perfect slider in monolithic terms.
Maybe that’s why the slider has frustrated researchers in the past. While we have a good idea about what makes a fastball good (ride and velocity), what makes a curveball good (velocity and drop), and the two types of changeups that are generally effective (power changeups with great movement and straight changeups with large velocity gaps) … the slider has been a living shrug emoticon so far.
Probably because the slider, as a pitch, acts a little like a changeup in one way: It interacts with the fastball.
“I think it’s a swing and miss pitch because it looks so much like a fastball,” slider master Corbin told me recently. “It comes out of the same slot and you can locate it well. The spin must look so much like a fastball, since they have so much trouble picking it up.”
Read the full article here (subscription required): https://theathletic.com/1133082/2019/08/13/sarris-what-makes-a-slider-good/
Originally published: August 15, 2019. Last Updated: August 15, 2019.