Sonny Gray and Pulled Ground Balls

There isn’t a top 75 pitcher that is as overrated by his ADP against his projections as Sonny Gray, it turns out. There’s almost 120 spots between where he’s being taken and where he “should” go, at least for now. You can see how that sort of thing happens.

He was 40th in strikeouts minus walks last season. 40th in strikeout rate. 26th in FIP. And ninth in ERA. And the ‘answer’ to that disparity is the worst in the business: he’s fifth in batting average on balls in play since he came into the league. 491 innings isn’t enough to believe that sort of things, so we all just whimper into our hats and wonder what to do about him.

The easy thing is to believe in the theory of DIPS, which says that a ball in play is a ball in play and it’s going to find grass 30% of the time. So regression will come for Sonny Gray. It probably will, despite the fact that a new slider has given him a legitimate third pitch.

But Gray has been excellent since he’s been in the league, despite average strikeout rates, and so it’s also tempting to wonder what he might be doing to deserve this batted ball ‘luck.’ Soft contact? He’s 40th. He *is* eleventh in ground-ball rate, and SIERA found a link between plus plus ground-ball rates and lower BABIPs. He’s 34th in SIERA since he came into the league. Sigh.

Here’s a weird thing. Gray is 25th in pull rate since he came into the league, and that plus the ground-ball rate might actually be part of the explanation. The pulled ground ball is death. It has the worst outcomes of any batted ball, even if it looks like it’s hit with authority. It is hit right at defenders, most likely.

So let’s look at the pitchers that are the best at getting hitters to pull ground balls!

Starting Pitchers and Pulled Grounder Rates
Name Pull GB% Pull FB% Pull GB/FB BABIP
Brett Anderson 25.5% 1.2% 20.54 0.318
A.J. Burnett 25.2% 1.9% 13.00 0.313
Dallas Keuchel 24.7% 2.1% 11.68 0.298
Charlie Morton 23.8% 2.1% 11.58 0.303
Tyson Ross 23.2% 2.0% 11.35 0.300
Trevor Cahill 24.5% 2.2% 11.20 0.314
Cliff Lee 18.7% 1.7% 10.72 0.308
Garrett Richards 24.9% 2.3% 10.69 0.279
Henderson Alvarez 22.6% 2.1% 10.54 0.294
Carlos Martinez 22.7% 2.3% 10.00 0.326
Felix Hernandez 27.2% 2.8% 9.82 0.285
Gerrit Cole 19.0% 2.1% 9.26 0.307
Justin Masterson 24.1% 2.7% 9.06 0.314
Francisco Liriano 21.7% 2.4% 9.03 0.288
Jarred Cosart 20.8% 2.3% 8.96 0.275
Wily Peralta 20.9% 2.4% 8.67 0.300
Sonny Gray 25.7% 3.0% 8.67 0.268
Jake Arrieta 19.2% 2.2% 8.61 0.254
Jeff Locke 23.8% 2.8% 8.49 0.291
Wade Miley 23.2% 2.8% 8.38 0.306
Sample Average 23.1% 2.3% 10.51 0.297
Minimum 1000 balls in play since 2013. Overall n = 140

The first sign that this does not explain Sonny Gray’s low BABIP is that Sonny Gray is ‘just’ 18th on the list. The second sign is that the bucket of the most extreme pulled ground-ball guys has almost a league average BABIP, and Gray is still an outlier.

This is a list of good pitchers, and they avoid the kind of power numbers that can inflate an ERA even with normal BABIP, but it doesn’t really provide us a magic bullet.

So we still haven’t explained Gray’s batted ball luck. Even if it’s tempting to point to his home park and team — the Athletics have the lowest batting average on balls in play since Gray entered the league — it doesn’t tell the whole story. Gray’s away BABIP is .276 for his career. He’s not even good at getting to two strikes, where BABIP is suppressed.

And when you’ve tried all you can to explain a thing, you shrug and rely on what pitchers have done in the past. You might want to believe the projections on Sonny Gray in 2016. At least until we better understand BABIP.

[Mea culpa: earlier version of this story had a field wrong in the query and was showing oppo grounders, that’s why the number was so low. Above is now correct for pulled grounders.]

We hoped you liked reading Sonny Gray and Pulled Ground Balls by Eno Sarris!

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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.

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Jetsy Extrano
Member
Jetsy Extrano

Those ratios seemed crazy high, until I realized that pulled airballs are hit with the bat accelerated forward in the zone, but a lot of pulled groundballs are just bounced off the bottom of a diagonal bat (bat head lower than hands), not forward in the zone.

Can we have two terms to distinguish? Balls you “top” by making contact below the bat axis, versus balls you “lead” by making contact with the bat advanced far around. Both tend to go to the pull field, assuming the bat is below horizontal and above vertical.

Jetsy Extrano
Member
Jetsy Extrano

(Matt Lentzner’s great 2007 article on this stuff has diagrams that explain the geometry better than words do.

http://www.hardballtimes.com/why-flies-go-one-way-and-grounders-go-the-other/

One of my favorite articles of all time.)