The Adjustment Clay Buchholz Made

Ever since (and including) a three-inning relief appearance against the Angels on July 31, Boston right-hander Clay Buchholz has recorded some promising numbers. In terms of run prevention, he’s been great: a 2.85 ERA in the American League is about 36% better than league average. By underlying factors, meanwhile, he’s been solid. His strikeout- and walk-rate differential (K-BB%) has actually been below average. By avoiding the home run, though, his fielding-independent numbers have been better than league average. Maybe he’s made a real change!

Poke around in his pitching mix, look through his pitches, and you might return to those luck factors, though. For one, a big part of what’s been different has been a return to the four-seamer. His worst pitch.

Buchholz’s four-seamer gets below-average whiffs (4.5%) and, over the last two years, terrible ground ball rates (33.9% and 35.4%, respectively). His sinker gets more whiffs (5.0%) and grounders (65.7%) — which probably explains why, over the course of his career, he’s gradually increased his usage of it. But not since the end of July. Here comes the four-seamer again:


It’s not quite all the back, but we can call it a renaissance. A weird one, though, considering the quality of the pitch.

Buchholz’s work against lefties gives us a clue as to why he’d return to the four-seamer. After four months of running fielding-independent numbers over six, with terrible walk and home-run rates against lefty batters, Buchholz hasn’t given up a home run to a lefty since July began.

Today’s starter for Boston has upped his four-seam usage against lefties 50% in the last two months, and he’s tightened the focus on the pitch. Inside, but as a strike — or, alternatively, high and out of the strike zone — is where he’s been throwing it since late July (right):


That location above the strike zone is the same one Buchholz cited recently when talking with our own David Laurila about the four-seam. “Up until this year, I’ve never really intentionally thrown fastballs up in the zone,” the Sox righty said. “I’ve started doing that, and whenever I execute, it works out. Above the zone, above the belt, or maybe belly-button high at the top of the zone.”

Of course, more four-seamers means fewer sinkers — although Buchholz has changed his approach with the latter pitch, as well. He used to throw the sinker low and away, the Leo Mazzone special. A few front-door sinkers were sprinkled in, but as the heat map on the left illustrates — featuring Buchholz’s two-seam locations until late July — it was all low and away early this year.


The heat map on the right, meanwhile, depicts Buchholz’s two-seam location since that late-July appearance. One finds a much more even split between inside and outside sinkers late this season.

When we look at small-sample in-play results on a pitch, we risk reacting too much to a few things that have gone wrong. But if you consider how predictably Buchholz was using his sinker before, and how his approach has changed, maybe it’s not so strange that his results on the pitch have changed — or that his results against lefties have improved.

As the pitcher told Laurila, league changes mean the pitcher has to change. Buchholz told Laurila that the “game has evolved.”

He continued:

“When I got called up, a lot of guys were high-ball hitters. They would take that pitch and hit it out. You were taught to throw the ball down, down, down. Now everybody is worried about their bat path and how they can get that ball going down and lift it. There are a lot more low-ball hitters in the game today than there were 10 years ago.”

Objectively speaking, Clay Buchholz’s four-seamer is his worst pitch. It’s straight relative to other four-seamers. It doesn’t have great sink or ride. It features just average velocity these days. His sinker, meanwhile, gets nice sink and fade; his change has a great velocity gap; his curve is relatively fast; and his cutter looks effective. If you were looking at his mix, you’d probably recommend something like 75% sinkers.

Except then you become predictable. You become that righty, throwing sinkers low and away to left-handers who have developed a bat path to destroy exactly that pitch. Sometimes, seeing that lefties are hanging over the plate and whooping your sinker is good enough reason to change it up — and to start throwing more four-seamers and front-door sinkers. Even if they aren’t objectively your best pitches.

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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7 years ago

Damn, I was hoping the answer would be the brand of cooking oil he slathers on his mane every day of his life.

7 years ago
Reply to  O'Kieboomer

I was hoping less time in between pitches.