Pitchers Who Pitch to Their VAA

When something becomes sexy, I’m all in. Crocs and socks? Sexy. Minivans with a built-in vacuum cleaner to suck up all the floor Cheerios? Sexy. Throwing a four-seam fastball with a very shallow vertical approach angle due to some serious induced vertical break at the top of the zone? Sexy. Some things some people just can’t pull off. But when a trend becomes a trend, you’re either in or you’re out.

Measuring the shape of a fastball with multiple data points and summarizing that into a score is an overly simplified way of explaining how Stuff+ and PLV work. Alex Chamberlain does great work with his pitch leaderboard making metrics like vertical approach angle (VAA) and horizontal approach angle (HAA) available to analysts, baseball nerds, and baseball couch potatoes alike. After seeing Alex’s presentation at PitchCon2o24, I was interested to know on a large scale which pitchers are pitching as their VAA plays best. If you’ve never heard of VAA before, you should start with Chamberlain’s primer article, jump to Simple Sabermetrics’ video overview, and then, if you’re looking for a pallet cleanser, head on back to this article.

You can also just choose to stay here noting that VAA is simply the angle at which a pitch enters the zone measured below the flat, horizontal line that extends from the mound to the plate. Gravity will force all pitches to enter with a negative angle, but some pitchers can make their fastballs flatter, or less negative, than others. Spencer Strider is the poster child for throwing a flat fastball and like Chamberlain’s research points out:

we celebrate flat four-seamers up (with gutsy, elite four-seamers down the middle), steep sinkers down, all kinds of breaking and off-speed pitches down, and a hanging secondary in favor of a hanging fastball.

I want to know who did that (^) in 2023. Or, more specifically, this:

  1. threw a four-seamer at the top of the zone (Statcast zones 1, 2, and 3) more than 20% of the time.
  2. had a vertical approach angle above average (VAA AA) or greater than 0.
  3. threw a four-seamer with an average velocity greater than or equal to 94 MPH.
  4. threw more than 1,000 four-seamers in 2023.

That’s all to explain a fast, flat fastball up in the zone often. Whew! Still with me? Who has demonstrated the above with regularity?

Fast Flat Fastballs Up in the Zone
Name Pitches VAA VAA AA Velo (MPH) % of Pitches Up
Gerrit Cole 1739 -4.3 0.17 96.4 23.9%
Spencer Strider 1698 -4.1 0.34 98.3 22.4%
MacKenzie Gore 1464 -4.4 0.02 96.2 21.7%
Freddy Peralta 1453 -3.7 0.75 95.5 22.5%
Michael Kopech 1431 -4.1 0.30 96.0 21.3%
Luis Castillo 1423 -3.8 0.64 94.8 25.9%
Jesús Luzardo 1375 -4.4 0.01 95.4 22.4%
Zack Wheeler 1370 -4.0 0.46 97.5 25.3%
Ken Waldichuk 1344 -4.2 0.22 94.4 21.0%
Ryne Nelson 1285 -4.4 0.02 95.0 23.3%
Bryce Miller 1224 -4.0 0.40 95.0 23.0%
Hunter Greene 1135 -4.4 0.04 97.6 23.5%
George Kirby 1112 -4.4 0.04 96.4 30.8%
Dean Kremer 1084 -4.3 0.15 94.4 23.3%
Pablo López 1043 -4.2 0.25 96.7 26.2%
Grayson Rodriguez 1043 -4.2 0.24 98.6 24.7%
*VAA AA is not adjusted for pitch height yet isolated to Statcast zones 1, 2, and 3
**Up relates the percentage of total four-seamers in zones 1, 2, and 3

Let’s take it a step further and look for the pitchers from the list above who also throw a significant portion of their breaking pitches, in this case, sliders, curveballs, and sweepers, low in the zone (Statcast zones 7, 8, 9, 13, and 14). I’ll also bring in overall Stuff+ metrics to add a little color:

Good Fastballs Up, Lots of Breaking Balls Down
Name IP % of Good Fastballs Up % of SL, CU, ST Down Stuff+ Location+ Pitching+
Hunter Greene 112.0 23.5% 67.0% 123.6 102.8 107.0
Zack Wheeler 192.0 25.3% 84.5% 109.2 105.7 111.4
Luis Castillo 197.0 25.9% 75.1% 96.0 103.5 101.7
Freddy Peralta 165.2 22.5% 71.9% 102.9 101.6 104.9
MacKenzie Gore 136.1 21.7% 69.0% 100.6 97.5 100.6
Spencer Strider 186.2 22.4% 76.7% 124.6 104.1 111.9
Gerrit Cole 209.0 23.9% 72.5% 121.0 103.7 108.8
**Down relates the percentage of sliders, sweepers, and curveballs located in zones 7, 8, 9, 13, and 14.

Grayson Rodriguez, Dean Kremer, George Kirby, Bryce Miller, Ryne Nelson, Ken Waldichuk, and Michael Kopech fall off as they aren’t locating their breaking balls low in the zone often enough. Let’s take a look at George Kirby’s heat map to see why he falls off:

George Kirby SL Location

I’d venture to say that Kirby is locating his slider very well against righties, but could benefit from lowering the pitch slightly to lefties. Here’s a comparison of how the pitch performed against batter handedness:

VS Righties

  • BA: .246 xBA: .248
  • SLG: .333 xSLG: .360

VS Lefties

  • BA: .306 xBA: .321
  • SLG: .472 xSLG: .390

I’m not smart enough to make recommendations to major league pitchers, but I did stay at a Holiday Inn last night and George Kirby might benefit from throwing the slider less often to lefties.

Instead of looking at the pitchers who throw high and low with effectiveness, let’s just look at the pitchers who throw steep sinkers low in the zone. Ben Clemens detailed the Giant’s usage of sinkers low in the zone and their ability to garner called strikes. It’s a great read. Pitchers who have taken to this new trend seem to have something going for them. Who sat at the cool kid’s table in 2023?

Steep Sinkers Low in the Zone
Name Pitches VAA VAA AA Velo (MPH) % of Pitches Down
Sandy Alcantara 579 -6.6 -0.14 97.1 30.6%
David Peterson 536 -7.2 -0.79 92.7 22.6%
Patrick Corbin 499 -7.0 -0.55 92.5 50.9%
Ranger Suárez 419 -6.9 -0.43 92.8 31.0%
Adrian Houser 414 -6.8 -0.34 93.2 47.6%
Kyle Gibson 407 -7.2 -0.76 93.0 41.5%
Michael King 378 -6.5 -0.09 93.9 29.9%
Touki Toussaint 375 -6.5 -0.03 94.1 25.3%
Javier Assad 328 -6.6 -0.14 93.1 32.0%
Jordan Montgomery 312 -7.4 -0.92 93.3 72.1%
Dakota Hudson 287 -7.3 -0.85 92.2 41.1%
Paul Blackburn 272 -6.6 -0.18 92.1 29.0%
Noah Syndergaard 254 -6.9 -0.41 92.7 31.1%
Jhony Brito 246 -6.6 -0.17 95.7 22.0%
*VAA AA is not adjusted for pitch height yet isolated to Statcast zones 7, 8, and 9
**”Down” is the percentage of total four-seamers in zones 7, 8, and 9
***Among pitchers who threw more than 200 sinkers in 2023

Oddly enough, no pitchers are sitting in both sections of the cafeteria. Four-seam cool kids and sinker cool kids are forming separate gangs. From a fantasy perspective, it’s nice to see who is practicing the skills that have been proven successful. There are a few names in these tables that might spark a little more digging. Some can likely be ignored. But I certainly remember going through a bit of a persona change in middle school when I finally ditched my crummy winter coat for a pull-0ver Starter jacket and became, finally, cool. For about a week, at least.

What’s in is in, no matter how you feel about it. It’s 2024! People are wearing headphones with wires again, sneakers just keep getting stranger, and soon we’ll all be walking around with computers that look like snow goggles shielding our faces. What will happen to fastballs? Sinkers? Breaking balls? We’ll just have to wait and see.





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JonathanGalt
1 month ago

Starter pull-over jackets? Be still my heart. What team were you rocking? I got my disgusting aqua Miami Dolphins Stater jacket in grade 5. I’ve never been as cool since.

Mario Mendozamember
1 month ago
Reply to  JonathanGalt

no single item ever imparted more instant coolness than a Starter jacket circa 1991