Daniel Norris, Justin Verlander, and the Tiger Slider

Don’t ask Justin Verlander if his new harder slider is a cutter, apparently. “Verlander is steadfast on this — he’s not throwing a cutter. It’s a slider,” is how Chris McCosky characterized the ace’s opinion on the changing pitch.

The difference between a cutter and a slider is difficult to really nail down — and is most easily represented as existing on a spectrum. First, there’s the cut fastball, thrown with a slightly offset grip but still a fastball release. That pitch usually goes about a mile or two slower than the four-seam with only a couple inches of drop beyond the four-seam. Mariano Rivera threw that thing better than anyone, but Adam Ottavino modeled it for us.

Then there’s the baby slider, a cutter grip thrown with a little more supination before release, and those go 4-plus mph slower and have a few inches more drop. Those are the pitches you see from Madison Bumgarner, Cole Hamels, Jon Lester, James Shields, and Adam Wainwright. Most of those pitchers refer to that pitch as a cutter, but most of those pitches also drop more than the overall average for the cutter.

To make matters worse, there’s a brand of slider thrown by the Mets which might fit between the “baby slider” cutter and the slider-slider. We’ve dubbed that pitch the Warthen Slider. And it might be the answer to why Verlander is throwing a harder slider that looks like a cutter, but one to which he still refers as a slider. And it might be part of the answer to why tonight’s starter Daniel Norris has seen such an improvement in his walk rate.

Let’s return to that piece about the Warthen Slider to get a definition from the Mets’ pitching coach himself. “It’s a different spin, it’s a different grip,” is how the coach characterizes it. “The whole idea is not to use your wrist to try and spin the ball. You want your fingers to spin the ball. You’re thinking fastball and just kind of cutting through the ball.” If you’re looking for an example of the offering, consider basically anyone on the Mets pitching staff. Noah Syndergaard, Matt Harvey, Jacob deGrom, Jeurys Familia, Hansel Robles, Robert Gsellman, and Seth Lugo all throw it.

If we were to use numbers to describe the pitch, we could use those pitchers as a starting point, and say the following about the Warthen Slider:

  • It’s hard for a slider and soft for a cutter, about 4 mph slower than the fastball.
  • It has more drop than a cutter and not as much drop as the better sliders.
  • It’s a low-spin, high velocity slider, due to the mechanics.

So we can apply that rubric to the Tigers’ two fairly easily. Have their sliders gotten harder, retained more drop than the average cutter, and also lost some spin as the year has developed? In order to adjust for the fact that spin usually goes up with velocity, let’s reflect spin here as rpm per mph. Let’s also define velocity and drop against their fastball, since the fastball sets the tone.

Verlander & Norris, New & Old Sliders Against Average
Player Velocity Differential Drop Differential Spin/Velo
Average Slider 8.1 7.7 24.8
Verlander, Early 2015 7.1 5.8 27.4
Verlander, Late 2016 5.1 5.2 27.9
Norris, Early 2015 8.9 10.2 23.0
Norris, Late 2016 7.1 7.7 27.6
Average Cutter 3.8 3.1 24.7
SOURCE: Statcast, PITCHf/x
Average spin per mph is calculated from Mike Petriello’s post on average velocity and spin.

Maybe these aren’t quite Warthen Sliders because the spin has actually increased. If you express it as a raw unit or a unit per mile per hour, the spin on both Norris’ and Verlander’s new sliders has gone up a bit.

But it should also be immediately clear that calling these cutters is a bit unfair. Both go more than 5 mph slower than their fastballs, and the average cutter is usually at least a mile per hour closer to the fastball. The drop is where these pitches really separate themselves — these guys have the drop differential almost always associated with a slider. Only two of the 77 pitchers who have thrown a cutter and a four-seam 100-plus times this year have a bigger drop differential than Norris, and only 15 have a bigger differnetial than Verlander.

One thing for which cutters are known more than sliders is command. They’re thrown in the zone close to 53% of the time, while sliders are thrown in the zone 49% of the time — and there are fewer balls to called strikes in the cutter grouping than the slider grouping. Norris’ slider was a ball 50% of the time last year; it’s been a ball only 32% of the time this year. That’s huge for a guy who has had issues with walks. Verlander’s change has been a little bit less drastic, but in the right direction. This new slider gets more swings in both cases.

Verlander & Norris, New & Old Slider Outcomes
Pitcher Ball% Swing% Whiff%
Verlander, 2015 34% 53% 16%
Verlander, 2016 32% 58% 15%
Norris, 2015 50% 37% 9%
Norris, 2016 32% 57% 17%
SOURCE: BrooksBaseball

So it’s the best of both worlds. This new pitch has the drop and velocity gap (and whiffs!) associated with a slider, but the command outcomes associated with a cutter. You can call it a hard slider, a Tiger slider, a proto-cutter, call it what you will. It’s working.

With a phone full of pictures of pitchers' fingers, strange beers, and his two toddler sons, Eno Sarris can be found at the ballpark or a brewery most days. Read him here, writing about the A's or Giants at The Athletic, or about beer at October. Follow him on Twitter @enosarris if you can handle the sandwiches and inanity.

Newest Most Voted
Inline Feedbacks
View all comments
6 years ago

Norris is one of those guys it feels like I have been hearing about forever. Then I look and he is only 23. I hope this sticks for him. Very interesting Eno!

6 years ago
Reply to  bkgeneral

Not only is he young, but he really hasn’t gotten much of an opportunity. He has been optioned to the minors more times than just about anyone of his age and pedigree.

6 years ago
Reply to  RonnieDobbs

Because he’s either hurt or pitching terribly…It’s not because he hasn’t been given a shot.

6 years ago
Reply to  RonnieDobbs

Really? Seems like he’s been optioned twice. Most guys his age aren’t in the majors yet. Add in two oblique injuries, hairline fractures in his vertebrae this spring, and thyroid cancer, and I don’t think opportunity has been the issue. Just finally good to see him healthy for a few months straight so he can finally start building on his progress. Curious to see his last start today.