Ground-Ball Benchmarks for Pitch Types by Eno Sarris April 15, 2014 Swinging strikes are half (more than half?) the battle. But you can use pitches for grounders, too. Take Marco Estrada, for example. By whiff rates, his change (18.4%) is plus, but his curve (9%) is not. That’s okay! By grounder rate, his curve is plus plus (60.8%). That means he has two great secondary pitches and qualifies to be a Guy I Like. In order to help you spot good grounder pitches, I’ve run the benchmarks on each pitch type below. Should pair nicely with a Cabernet and this post which shows the benchmarks for whiff rates per pitch type. Ground ball rates by pitch type: Pitch League GB% Four-Seam 37.9% Cutter 43.0% Slider 43.9% Change 47.8% Curve 48.7% Sinker 49.5% Four-seamers aren’t for grounders. Someone forgot to tell Garrett Richards (58% last year), and the top ten starters are mostly very interesting: Richards, Tyler Chatwood, Doug Fister, Dallas Keuchel, John Lannan, David Price, Tyson Ross, Andrew Cashner, Tanner Scheppers, and Sonny Gray. All with better than 50% ground-ball rates on the pitch that’s worst for grounders. That puts you on the right track, and it probably also means you keep the ball down most of the time. The cutter and the slider have very similar movements, so it’s not too surprising to find them next to each other. Used more for whiffs than grounders, these breaking pitches still turn into grounders in the right hands. Jenrry Mejia (60%), Drew Smyly (58%), Cole Hamels (57%), and Gerrit Cole (55%) all throw cutters for grounders. Just another reason to love Mejia. On the slider side, Brett Anderson (71%), Tyson Ross (65%), Tyler Chatwood (again! 61%), Hyun-Jin Ryu (59%, which is good because his swinging strike rate isn’t great on the pitch), Matt Moore (58%, condolences), Chris Tillman (57%), and Felix Hernandez (56%) get good grounders on their slide pieces. Interestingly, the curve has moved ahead of the change as a pitch for ground balls. That might be because fewer batters swing at the curve than at any other pitch, so it’s not a great pitch to use for whiffs. The curve usually ends up down in the zone, good for grounders, but so does the change. Atop this new curves-for-grounders scheme sits Alex Cobb, who got an insane 74% grounders on his curve last year. Other notable starters include Jeremy Hellickson (65%), Mike Minor (64%), Gio Gonzalez (63%), Stephen Strasburg (63%), Mike Leake (61%), Matt Harvey (swoon, 61%), David Phelps (61%), Mat Latos (60%), and Lance Lynn (59%). Rick Porcello (58%) is right there, too, which is notable since the curve is a new pitch for him. Even if you add split-finger “change-ups” into change-ups, you only push the grounder rate to 48.1%, not quite curve territory. In terms of true change-ups, there’s a great trio atop the grounder leaderboards: Carlos Carrasco (70%), Corey Kluber (69%) and Michael Wacha (67%) look like they belong. And then you have Stephen Strasburg (63%), who’s atop all leaderboards ever. Alex Cobb (60%), Tim Lincecum (60%), Jon Lester (60%), Andy Pettite (60%), Matt Harvey (60%), and Adam Wainwright (60%) all make sense. You might be surprised to see Charlie Morton (60%), Philip Humber (60%), Zach McAllister (60%) Miguel Gonzalez (59%), and Jose Quintana (58%) up there, though. And then there’s the sinker, the pitch born to birth ground balls. Among starters, it’s no surprise to see Charlie Morton (66%), Justin Masterson (65%), Rick Porcello (64%), and Tim Hudson (64%) leading the way. But the next group is also interesting: Andrew Cashner (64%), Lance Lynn (63%), Dallas Keuchel (again! 62%), Ivan Nova (61%), and Brandon McCarthy (60%) all let their sinker speak for them. A.J. Burnett hasn’t been throwing his sinker very long, but at 58%, it’s doing it’s job. In particular, make sure to hang a look at the ground-ball rate before you kill a pitch. It certainly helps you understand how Ryu’s slider or Estrada’s curve are still strong pitches. Next up: Z-scores for whiff rates and grounder rates. And at some point, an arsenal evaluation number.