What Changed for Homer Bailey in Oakland?

Please Credit: Kelley L Cox-USA TODAY Sports

The Minnesota Twins signed a pair of starting pitchers on New Year’s eve — and it’s fair to say Rich Hill received more fanfare of the two.

While Homer Bailey‘s deal was for more guaranteed money — $7 million to Hill’s $3 million — it was Hill who received more digital ink spillage over the days that followed the agreements.

It’s not entirely unreasonable to surmise that Hill was more talked about due to his pedigree (3.00 ERA over the last four seasons), health (primary revision surgery in November) and the team he was defecting from (Los Angeles Dodgers), but the reality is that Bailey is going to make a more immediate impact on the Twins’ pitching plans.

There are a lot of ways to remember Bailey’s career to this point. One could remember the hot-shot prospect from more than a dozen years ago, the pitcher who pitched well enough to earn a $100 million-plus contract, the pitcher whose injuries turned him into a salary dump at the end of it or more recently, the pitcher who is coming off a bounce-back season of sorts — split between the Kansas City Royals and the Oakland Athletics.

The stint with the Royals was enough to get him traded to a contender near the deadline, but we’d like to narrow our focus to just his time with the A’s. Rather, we’d like to go down that road and perhaps even more narrow — the final two months of the 2019 season.

When the Royals inked Bailey a little over a year ago, it was as a reclamation project of sorts. The righty had only thrown 231.2 innings over the previous four seasons — and at a 6.25 ERA. And while Bailey’s numbers weren’t terrific with the Royals — 4.80 ERA (4.48 FIP) in 90.0 innings with 8.1 K/9, 3.8 BB/9 and a 1.41 WHIP — clearly Oakland saw enough from him to think they could help him with a tweak or two.

So what were those tweaks?

Bailey made his Royals debut at home against the Twins on April 3, and from the following image, we can see that he sets up fairly far over on the right side of the pitching rubber.

(please credit: screenshot)

It might not be something fans think about much, but where a pitcher sets up on the rubber is definitely a big part of how they conduct their business. It was a concept Kyle Gibson explained to me while writing for another publication, and it’s one that’s pretty easy to understand. Different spots on the rubber do different things for pitchers based on handedness and repertoire, among other things.

For a righty who throws a certain type of slider, it might make more sense to start from the far right of the rubber. In that case, the righty can front-door a slider on the inside corner for a strike against a right-handed hitter. The gist of it is this: some pitches make sense to have out of the strike zone for as long as possible on the path home before breaking across the plate late. Other pitches might be better used starting in the strike zone but exiting, again, late in the trajectory home.

So when we examine where Bailey sets up, we have to consider this.

In his first Oakland start, July 17 against the Seattle Mariners, it’s clear he’s moved a little bit. Independent pitching analyst Jeremy Maschino did a little digging and suggested Bailey moved a bit sometime in May, and while it isn’t always easy for the average fan to figure out statistically — based on scatter plots, numbers and that sort of thing — an easier tell is where his toe is in relation to the edge of the rubber in still photos grabbed at roughly the same part of his delivery.

(please credit: screenshot)

Flash forward to his penultimate start of the season — where he absolutely shoved against his old friends, the Royals — and it’s evident he’s fully committed to the middle of the rubber. Clicking the image to enlarge it makes it a little easier to see.

(please credit: screenshot)

In that game — part of Bailey’s blistering hot run to close the season — he threw seven shutout innings with three hits, 11 strikeouts and just one walk as the A’s beat the Royals, 1-0.

Now moving to the center of the rubber would seem to carry two possible complications — one good, one bad.

The bad would seem to be that hitters, especially righties, would have more time to pick up breaking stuff out of the pitcher’s hand.

To combat this, Bailey simply threw more fastballs and splitters and fewer breaking balls:

(please credit: Brooks Baseball)

As it turns out, that concern was probably justified. Here are the slugging percentages allowed based on his time in Kansas City and Oakland on each pitch type he threw. Ignore the sinker — he barely threw it in Kansas City and scrapped it entirely with Oakland:

(slugging percentage against by pitch type with Kansas City, please credit: Brooks Baseball)
(slugging percentage against by pitch type with Oakland, please credit: Brooks Baseball)

The good, and perhaps obvious, effect of moving toward the middle of the rubber is having more of the strike zone to work with. Now that can cut both ways as pitchers who live in the strike zone can be hit hard — think Brad Radke on his worst days — but for Bailey, it seemed to be pretty obviously a good thing.

On the surface level, he managed to increase his strikeout rate (20.8 percent to 22.2 percent, 8.1 K/9 to 8.4 K/9) and oddly enough, missed more bats (11.0 percent swinging-strike rate with Oakland to 10.6 percent with Kansas City) despite going more fastball-heavy.

Now again, this can cut both ways. His rate of pitches in the strike zone jumped from 41.6 percent to 44.0 percent with the move to Oakland, but it also coordinated with an increase in zone contact rate (85.2 percent to 87.6 percent). However, it seems to correlate with a welcome drop in contact rate outside of the strike zone, falling from 66.0 percent with the Royals to 60.8 percent with the A’s. With a 1.5 percent bump in swing rate outside of the zone and the added drop in contact out there, it’s probably fair to say it was a good tradeoff.

That might be underselling the easiest thing to take away from it all — the drop in walk rate. Bailey walked 3.8 batters per nine with the Royals for a 9.8 percent rate — exactly what Luis Arraez did last year, for context — but those marks dropped to just 1.8 batters per nine and a rate of just 4.9 percent. That’s basically what Danny Santana, the notoriously swing-happy former Twins infielder, did with the Texas Rangers last year.

I’m no math major, but cutting one’s walk rate in half seems like a very good thing.

Making a move on the rubber to likely diminish the efficacy of both of your breaking pitches is a risky move, but it seems to have paid off for Bailey. And it makes sense; while it effectively neutralized the value of his slider and curve, they were a) his two least-thrown pitches on a regular basis and b) not all that special to begin with.

That he was able to make these moves on the mound and not get absolutely bombed — his home-run rate actually dropped with Oakland in the year of the homer, though that’s probably more a credit to his new ballpark — is a credit not only to the A’s for their pitching wizardry, but Bailey as well for being willing to go along with any changes suggested.

For added context, opponents hit .258/.332/.409 off Bailey with the Royals and .254/.294/.397 with the A’s. The only real significant change is the on-base percentage — and it’s a welcome one. The difference between allowing an isolated discipline (OBP-SLG) of .074 to .040 is like going from Nelson Cruz to Eddie Rosario.

That’s a massive difference.

One other thing Bailey did with Oakland that Maschino helped quantify was that his release height was higher with the A’s than with the Royals.

(image furnished by Jeremy Maschino)

For a low-spin guy like Bailey, Maschino reasoned, that change made a fair bit of sense.

(please credit: Baseball Savant, Statcast)

“Because Bailey is a low spin guy, creating a large attack angle and attacking the lower-third of the zone is where he is going to thrive,” Maschino said. “By raising the his release height with all of his pitches, and continuing to attack the zone — especially with his low spin four-seamer and splitter — they will look like they are going to hit that bottom-third and then fall out of the bottom of the zone. This causes hitters to swing over the ball and creating more favorable ground ball results.”

Maschino’s theory holds water. While Bailey induced grounders at a lower rate with Oakland, that’s less problematic when considering he a) traded some of them for popups, which are almost always outs and b) the Coliseum plays much bigger than Kauffman Stadium.

Statistically, opposing batters hit .256/.256/.289 on grounders when Bailey was with Kansas City for a wOBA of .234. With the A’s, the slash was .237/.237/.237 — a wOBA of .206.

Ultimately, the A’s proved it was possible to teach an old (willing) dog new tricks.

The impetus will be on the Twins to show they can keep it going.

Jeremy Maschino contributed research to this article.

Twins Are Betting On a Literal Change Of Scenery To Unlock Mahle
By Tony Abbott - Aug 5, 2022
Michael Fulmer Is the Dessert After A Delicious Trade Deadline
By Lou Hennessy - Aug 4, 2022

Why Tyler Mahle's Stat Line Is Deceiving

Please Credit: Kelley L Cox-USA TODAY Sports

Hey, the Minnesota Twins finally added some impact pitching! They added starting pitcher Tyler Mahle from the Cincinnati Reds in exchange for a trio of prospects: Spencer […]

Continue Reading