Locke St. John and the Lateral Movers

Last week, I wrote about the handful of pitchers who drop their release points significantly when facing same-sided batters. Today I’m going to highlight a few who change their release points by a different method. Before we get to them, I’d like to talk a bit about why anybody would risk messing with their release point in the first place. This is an article about the potentially transformative power of scooching over.

I started thinking about arm angles with a very blunt test. For the last seven years, I pulled every pitcher’s average release point and their wOBA against lefties and righties, then calculated the correlation between them. I also pulled average velocity as a control variable of sorts. The correlation coefficients are small, but they line up with what we’d expect:

Unsurprisingly, it’s always good to throw the ball hard. Against same-sided batters, pitchers who release the ball lower and wider fare better. Against opposite batters, a wide release point is associated with poor results.

Despite the clumsiness of this method, there’s still a surprising amount of signal. Against same-sided batters, average velocity and average vertical release have an equal relationship to overall performance! I certainly didn’t expect that, especially when you consider that average velocity and vertical release point have their own correlation (r=.15). Lower release points are more successful despite the lower velocities that come with them.

Next, I looked at data on individual pitches. I bucketed every pitch thrown in the Statcast era in groups of two-tenths of a foot (2.4 inches), and pulled the average wOBA for each. Starting with vertical release point, here are same-sided batters:

That is a very convincing graph. The lower the release point, the harder it is for same-sided batters. For every extra inch of height, wOBA goes up roughly 1.4 points to righties, and 1.2 points to lefties. Now that we’re looking more granularly, the correlation between release point and wOBA is extremely strong. For righties, the correlation coefficient is an astounding .96. For lefties it’s .73. Here’s the same graph for opposite-handed batters:

This trend is definitely weaker, but it’s still there. For each extra inch of height on the release point, lefties allow 0.8 extra points of wOBA; for righties it’s 0.6. The correlation is -.56 for righties and -.59 for lefties.

To this point, I’ve been using vertical release point as a proxy for arm angle, but it’s not that simple. Variations in height, wingspan, and mechanics mean that the equivalence between the two is imperfect. You can reverse engineer arm angle from PITCHf/x or Statcast data, but that will only give you an estimate. I imagine Statcast is capable of tracking arm angle. If that data ever becomes accessible to the public, I think it might significantly change our understanding of the platoon advantage.

We’ll look at horizontal release point next, but there are two reasons that it’s not as good of a proxy for arm angle. The first is that horizontal release point stops working for pitchers who drop down dramatically. If you’re a righty, your horizontal release point will decrease as your vertical release point decreases, but once you pass 90 degrees, that relationship flips. The second is that the pitching rubber is 24 inches wide, and players can and do stand wherever they want on it. To demonstrate, I took some screenshots from last season’s ALDS Game 3 between the Astros and the Mariners. It was the first game I could think of that featured a whole lot of pitchers:

These are just the first seven righties I saw, and the positioning variety is obvious. If you focus on each player’s back foot (or their butt, if you enjoy that sort of thing), you’ll see that even on the same teams and with the same pitching coaches, everyone has their own spot where they’re comfortable. And players really do stick to that spot. Most pitchers have less than an inch of difference between their horizontal release points to lefties and righties, and over 94% are within three inches. Those numbers get even higher if you remove all the position players pitching. However, as is always the case, there are some guys who take things way too far. It’s time for the scoochers.

Maybe the platoon advantage exists because of arm angles and the different movement they can generate, and maybe it exists because of the difficulty in picking up a pitch that starts out way behind you. If it’s the latter, then shouldn’t pitchers stand all the way on the batter’s side of the rubber regardless of their arm angle? There are five major league players who seem to think so:

Yankees left-hander Wandy Peralta seems comfortable pretty much anywhere on the mound. Depending on the handedness of the batter (and other factors about which I have no clue), he’ll pitch from the far left, middle, or far right:

Peralta used to stand off to the left against everyone, but he started shifting toward third base in 2020, then took a leap of nearly a foot from ’21 to ’22. That move also coincided with a career year, though Peralta’s performance improved more against lefties than it did against righties.

Right-hander Chase Anderson has serious reverse splits, an understandably common trait among the pitchers on our list. Over the course of his nine-year career, the 35-year-old has a .298 wOBA against lefties and a .353 wOBA against righties. Anderson is a serial scoocher. He’s shifted his positioning on the rubber in just about every year of his career. He first went full-on splitsies in 2018, setting up eight inches apart against righties and lefties, then increasing that gap to more than a foot in 2019. However, he abandoned the practice in 2021, when, coincidentally or not, he posted a career-worst .446 wOBA against righties. He went back to his old ways in 2022.

Rookie Jared Koenig made just 10 appearances in 2022, but he also had reverse splits in his 37.1 innings; he allowed a .411 wOBA to lefties and a .310 wOBA to righties in that small sample. Koenig is a currently a free agent after being non-tendered by the A’s.

Our last two players take this exercise much more seriously. Matt Strahm’s release point against lefties is just over a foot and a half wider than his release point to righties. Strahm also has reverse splits, though they’re not egregious. He has a .314 wOBA against his fellow southpaws, and a .296 wOBA against righties. Strahm has been drifting toward first base against lefties since the beginning of his career, even though to my eye his arm angle has risen slightly. In 2019, his release point jumped a full foot to his current position. Sometimes his foot barely even touches the rubber against lefties. In fact, if double-barreled action is your thing, there’s plenty of room for the lefty-facing and righty-facing versions of Strahm to share the same mound:

Last and certainly not least in the name department is Locke St. John. For the record, his full name is Kenton Locke St. John, which indicates that he’s either an honorable southern gentleman or a scrappy Boston law firm. St. John only played in one game during the 2022 season, but he made sure to do so in memorable fashion.

St. John treats the mound like his own personal slalom course. The gap between his setups is nearly double Peralta’s, and again, Peralta has the fifth-highest gap in the league. St. John sets up so far to the left against lefties and so far to the right against righties that there’s actually enough space for a third Locke St. John to set up snugly in the middle:

The Locke St. Johns on the left and right are actual screenshots of where he sets up. The one in the middle is purely hypothetical, but the massage train feels very real to me. In fact, St. John sets up so far to the edges of the rubber that were he involved in some sort of Multiplicity situation, he could pitch right next to himself quite comfortably. I did my best to split these two pitches right at the center of the mound.

St. John made seven appearances with the Rangers in 2019. He featured a significant gap then as well, but when he reemerged last season, he set up an extra 8.5 inches closer to third base against righties than he had in ’19, nearly twice the rate of continental drift. The Mets picked St. John up on waivers after his one 2022 appearance with the Cubs. He was outrighted in June, and is currently a free agent.

Now that we’ve had a chance to savor the Locke St. John of it all, let’s return to the question: Are these five players on to something? Here are the same charts I showed you before, but with horizontal release point swapped in for vertical. For the sake of interpretability, I’ve inverted the numbers of righties so that they’ll match up with those of lefties:

There are definitely still trends despite the noise. However, if you look more closely at the same side chart, you’ll notice that both lines are fairly flat until the 2.5-foot mark. At that point, the data has a survivorship bias for pitchers who drop down. To look into that further, I focused on right-on-right matchups, splitting the data between pitchers who drop down and pitchers who don’t. I set the dividing line at five feet, which for most pitchers should be something like a three-quarters delivery:

For the pitchers who don’t drop down at all, there’s not a particularly strong trend to speak of. The correlation is 0.15. There are fewer pitchers dropping down, so the data is both sparser and noisier, but the correlation is now the opposite of what we’d expect, at -.35. That is to say, the wider a righty sidearmer’s release point, the worse they do against righties.

If pitching from a wider spot on the mound helps, it doesn’t help enough for us to be able to detect it using these methods. However, it doesn’t seem to hurt much, particularly for pitchers with a standard delivery. Keep in mind, that’s taking the league as a whole; there could be individual pitchers who would benefit from it. Another trend that you might’ve noticed in these graphs is that the lines almost always seem to tick down towards the edges. As with so many parts of the pitcher-hitter relationship, the more batters see something, the better they handle it. If there’s a pitcher whose delivery would create an unfamiliar look at the far edge of the rubber, it might be worth investigating.

In my last article I wrote about players who drop down some of the time, which is a much harder adjustment for a pitcher to make and maintain. I don’t think it would be crazy for more pitchers to see if they feel comfortable scooching over against same-sided batters. I’m not particularly confident that it’d work, but I don’t think it’s a crazy thought. Besides, I’m in favor of any development that lets me type out the name Kenton Locke St. John more often.