Robert Gasser and the Value of Uniqueness

Stuff models? What about just being yourself?

Watching Major League pitching is arguably more exciting now than it has ever been. The average starting pitcher in 2024 is equipped with the arsenal of an early-2010’s high-leverage reliever, and current closers are continually pushing the boundaries of velocity and movement. As a result, teams have largely zeroed in on a specific set of attributes they seek out in pitchers, placing an extreme emphasis on raw stuff and leaving little room for guys with more unconventional approaches by modern standards.

This has led to a fair amount of homogeneity among the top arms in today’s game. Think of the best pitchers going right now: Corbin Burnes, Tarik Skubal, Zack Wheeler, etc. These are all guys with explosive, high-velocity fastballs and wipeout breaking balls serving as the core of a diverse array of pitches. They represent the archetype teams are constantly trying to acquire and develop to build their pitching staffs. Their existence has pushed pitchers with less stuff to the margins of MLB rosters, destined to fill out the back of the rotation or act as nothing more than organizational depth.

With that said, I believe baseball is healthier and more engaging when there exist multiple pathways to success, especially on the pitching side of things. It’s always fun to watch pitchers dominate with power stuff, but I think it can be equally as entertaining when a guy like Ranger Suarez is performing like an ace by squeezing the most out of his arsenal with strong game planning and execution or when Logan Webb victimizes opposing lineups with his extreme movement profiles.

That idea is precisely why Robert Gasser has been one of my favorite young pitchers to watch this season. Contrary to what his name might lead to you believe, Gasser doesn’t possess a particularly electric fastball and isn’t singularly reliant on overpowering hitters. His stuff isn’t bad, mind you, but a large portion of his value is tied to the unorthodox looks he gives opposing batters in both his pitch arsenal and mechanics.

I want to go through everything that makes Gasser unique among his contemporaries and hopefully foster in the reader an appreciation for pitchers who leverage their eccentricities to produce results that most pitchers achieve through sheer force.


Secondaries First


Conventional pitching wisdom used to say that you should attack hitters with your fastballs first and put them away with breaking balls or offspeed offerings when you get to two strikes. Today, that notion has largely flipped on its head; we are seeing more starters lead the way with their secondaries than ever before. The Red Sox have made waves this season by throwing fastballs at a lower rate than any other team under the tutelage of Andrew Bailey, resulting in greatly improved performance from their pitching staff as a whole.

The idea driving this movement is that you want to throw your best pitch as often as you can, and for many pitchers, breaking balls produce the best results among their arsenal. If you had a pedestrian 93 MPH four-seam fastball as your primary hard pitch, but a deadly slider that produces whiffs at a much higher rate, why not lean harder on the pitch that gets good results more often?

In Gasser’s case, his go-to breaking ball is a lively sweeper with 15 inches of glove-side break at 81 MPH. This pitch has yielded the highest whiff rate among his arsenal at 34.7%, and the .191 opponent’s xwOBA against it suggests it hasn’t been hit with authority even when it is put into play. His other pitches have been solid to this point as well, but it’s easy to see why Gasser has been the most sweeper-forward lefty starter in the league and the second most sweeper-forward starter overall.


Highest 2024 Sweeper Usage% Among SP (min. 50 Thrown)


The sweeper is Gasser’s most frequently used pitch, thrown 10% more often than his four-seam fastball. That on its own would make him pretty unique among starters, but another interesting detail about his approach is that the sweeper is his most used offering to both left-handed and right-handed batters.

As the sweeper has become more prominent over the last handful of seasons, one thing that we’ve learned about it is that it is almost always more effective against same-handed hitters. From a hitter’s perspective, balls are easier to hit when they’re moving towards you and harder to hit when they’re moving away. It would make sense then that the sweeper, the pitch with the most horizontal movement in a pitcher’s arsenal, would fare much better moving away from same-handed hitters. That idea is apparent in Gasser’s sweeper usage, as he throws it over 50% of the time against left-handed batters. He still throws it almost 30% of the time against righties, more than his cutter and changeup, which are more conventional weapons pitchers use against opposite-handed hitters.

It’s not just Gasser’s usage of the sweeper that makes it a particularly unique offering. The pitch also features almost three inches less drop than the average left-handed sweeper with above-average glove-side movement and velocity. As I’ll discuss in a moment, Gasser’s low release height also factors into his sweeper’s individuality. A harder sweeper with more ride and glove-side movement from a low release point is a rare combination of attributes that hitters don’t see often, especially from a starter. Even more so from a starter who is unafraid to throw it against opposite-handed batters.



This confluence of factors likely explains why Gasser’s sweeper has performed comparably against righties as it has to lefties thus far. It’s been both his called strike weapon and his two-strike putaway pitch this season, resulting in an unorthodox matchup that leaves hitters in-between looking for the harder four-seamer and cutter or softer sweeper and changeup.

While Gasser’s pitch mix and usage have been the driving force behind his early-career success, his confounding of opposing hitters is also driven by his unique mechanics, particularly his low release point.


Coming From Down Low


With how much I like to talk about pitch shapes and how different movement profiles can improve or decrease the performance of a given pitch, you’d think that would be the only thing worth looking at when evaluating what makes a pitcher so hard to pin down. Arguably just as important as pitch shape, however, is where that pitch is coming from.

Take four-seam fastballs, for example. It’s all well and good if you have a four-seam fastball with great velocity and induced vertical break, but hitters have become more accustomed to seeing that profile in recent years and it’s much easier to generate that type of movement from a high release point. The absolute best four-seamers in the league have velocity and ride, but they also come from unique release heights that trick hitters into thinking they won’t carry as much as they do.

Paul Sewald is sort of the poster child for this idea. When you isolate his fastball to just movement specs, it doesn’t look like anything special. 14 inches of carry and 11 inches of arm-side wiggle at just a hair over 91 MPH doesn’t just look pedestrian, it looks downright bad. However, Sewald’s 4.5-foot release height is among the lowest in the league for a pitcher with 14+ inches of ride on their fastball, making it a supremely deceptive offering that has yielded good results year after year.

Gasser, meanwhile, has the fourth-lowest release point among all left-handed starters this season, giving his fastball a 1.5 height-adjusted vertical approach angle (HAVAA) that ranks in the 94th percentile among all starters. VAA is important for predicting potential performance indicators in fastballs, correlating particularly strongly with whiff rate. Below is a predicted whiff rate I’ve modeled against vertical approach angle for all left-handed four-seam fastballs this season.



If you’re looking to build an ideal fastball, good velocity and movement from a low release height is where you start.

It’s not just the four-seamer that benefits from this low release, either. Only JP Sears throws a left-handed sweeper from a lower release height among starters than Gasser, which likely contributes to its above-average horizontal break. In fact, looking at the rest of his arsenal, Gasser has among the most unique release points and movement profiles for pretty much every pitch in his arsenal.

He has the lowest release for a cutter thrown by a lefty starter with velocity almost two ticks above-average. His changeup has almost four inches more drop, four inches more arm-side movement, and is four MPH harder than average. Even his sinker, which is his most “normal” offering, still features more drop than average from the third-lowest release height among starters.

This is an arsenal that just exudes individuality and has driven Gasser to a fantastic start to his big-league career. The foundation of this arsenal is the unique angle at which he attacks hitters, which makes it much harder to reliably pick up on movement and creates a ton of deception inherent to his delivery.


Making Room For Weirdness


As I mentioned earlier, Gasser’s profile isn’t exactly one that Major League teams are foaming at the mouth to develop. He’s not overly velocity-reliant, he doesn’t have an overpowering fastball with tons of ride, and he relies more on his breaking stuff than any of his harder offerings to yield results.

Still, baseball is at its best when pitchers like this have a place on MLB rosters. More and more of the young starters making their way to the big leagues in recent years have fit the conventional “power pitcher” profile. Bryce Miller, Taj Bradley, Bobby Miller, and Eury Perez are among the most exciting high-octane arms to have debuted in the last two seasons, but all four have faced complications of their own en route to sustained success at the highest level.

I liken this discussion to the ongoing dialogue surrounding offense at the Major League level. Many fans have pointed out that games have become less engaging to watch with so many hitters prioritizing raw power over bat-to-ball skills, so MLB has responded by implementing rules that facilitate more contact, more stolen bases, and more action in general. The result has been a marginally more enjoyable product all-around.

Perhaps a similar effort should be made to allow more room for pitchers with unconventional pathways to success. I don’t think it would ever be feasible to penalize pitchers for throwing too hard or impose mandatory workload limitations, but some level of commitment to encouraging uniqueness would be a welcome sight.

Then again, there may be signs that this is already happening organically. Matt Waldron, for example, is the first honest-to-goodness knuckleballer we’ve had in years and he has a firm grasp on a rotation spot in San Diego. Maybe teams are starting to realize that less velocity-forward arms have become a market inefficiency in the modern pitching landscape.

What I’m trying to say can be boiled down to this: Robert Gasser, in a way, is representative of the Luis Arraezes of the pitching world. We love watching Arraez because he employs a different hitting profile than we’ve become accustomed to seeing with his extreme contact dependence, much as Gasser has with his sweeper usage and unique mechanics. They represent a breath of fresh air in what has become an increasingly homogeneous league. The more we are able to celebrate players with unique approaches to success, the healthier and more enjoyable the on-field product will be.

Pitching is an endlessly complex endeavor that I don’t think will ever be fully captured in any one player’s approach. Stuff models have been at the forefront of pitching development for the bulk of the last decade now, but maybe another movement is coming that still values stuff, but rewards pitchers who are as unique as possible in their approach. Maybe we’ll look back at Gasser as being among the first in that movement.


Photo by Larry Radloff/Icon Sportswire

2 responses to “Robert Gasser and the Value of Uniqueness”

  1. Jayjay says:

    Manager Pat Murphy said in his pregame session today that Robert Gasser is dealing with “some tightness, soreness” in his left (pitching) elbow and that he’s in the process of receiving a second opinion.

    • Michael Barker says:

      Ryan Pepiot went on the IL right after I wrote about him too. Maybe I should stop writing about specific pitchers :(

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