Davis Martin Kicks Into Gear
The indispensable role coaches play in development
Introduction
Pitching never fails to fascinate me. One of the most underappreciated aspects of baseball is understanding how impactful coaches are in development. The players ultimately are the ones that we watch and root for, but they likely wouldn’t perform at the highest level without the proper instruction and support. Pitching coaches have the ability to shape a pitcher's career, utilizing analytics to maximize their students' potential.
Davis Martin developing his new changeup is a prime example of how coaches can help redefine a pitcher. It was a group effort this time around, with a pair of pitching gurus turning Martin’s changeup from a middling offering into one of the most enticing pitches in baseball.
The Changeup Conundrum
Davis Martin is a supinator. This means that he can more easily rotate his arm to face his palm upwards while he struggles to twist it in the opposite direction (known as pronation). This lack of pronation was amplified following his Tommy John surgery in 2023. Martin states in an interview with David Laurila:
I’ve just never been able to pronate, and post-TJ it got even worse. I’m more of a supinator now than I was before surgery
This lack of inward rotation of his palm caused Martin to struggle to throw a changeup throughout his career. His changeup had decent characteristics in a vacuum, but its lack of vertical separation from his fastball made its effectiveness diminish. Following his TJS, Martin completely abandoned his changeup in his AAA rehab stint because his body would not permit it.
New Kicks on the Mound
Without his changeup, Martin’s future as a starter seemed to be in limbo. He wielded a 4-pitch arsenal but didn’t have a pitch that was effective against LHH.
Enter Brian Bannister and Ethan Katz.
Bannister is a Senior Pitching Advisor for the White Sox, and Katz is their pitching coach. Both Bannister and Katz are former professional baseball players and have been in development roles for over a decade and bring indispensable knowledge to the White Sox. Being in the game for so long exposes coaches to many pitchers, and over time, these coaches can pick up information and sense patterns that they can carry over. In Martin’s case, his arm action and high-spin profile mimicked that of San Francisco pitcher Hayden Birdsong, a pitcher that Bannister worked with previously.
Birdsong is an interesting pitcher because he, despite his supination bias, throws one of the nastiest changeups in baseball. This is because he employs a changeup that is able to maintain higher velocity with greater depth than a typical changeup thanks to his unique grip. Birdsong’s grip allows him to use his middle finger to “kick” the ball into its axis to generate side spin. Tread Athletics calls it the “Kick Changeup”.
Bannister, following his training with Birdsong, identified that Martin would be an ideal subject to learn this changeup. Martin’s introduction to the Kick Change is quite a fascinating story. Not only was the pitch easy to pick up on, but Martin felt comfortable with it after just 10 reps to add it to his in-game arsenal the very next day.
Martin posted the best game of his career, tossing 6.0 scoreless innings against the Athletics. Most impressively, he tossed 18 kick changeups after not throwing any in-game action prior. The feel for the offering only improved throughout the start as he continually hit the zone.
This pitch against Kyle McCann encapsulates the wickedness of the kick change. Martin registered 20” of arm-side run with this pitch and -1” iVB at 90 MPH. The pitch essentially moved like a left-handed slider from his right-handed slot. It’s no surprise Martin had McCann flailing at a pitch that landed in the dirt.
Familiar Change
Martin’s immediate success with his changeup was surprising to most, but not to Brian Bannister. Bannister wrote a wonderful thread about Martin on Twitter in August, where he highlighted his approach to pitcher development.
Instead of focusing on trying to wedge an unnatural pitch into an arsenal, he focuses on a pitcher’s biomechanics and introduces pitches and grips that fit their body. Bannister’s prior work with pitchers like Birdsong directly influenced his decision to introduce the Kick Changeup to Davis Martin.
It wasn’t simply just a coincidence that Martin found familiarity with his new pitch. Bannister leveraged his prior experiences to help Martin develop a wicked changeup in a single afternoon.
Change For The Better
Martin’s new changeup didn’t just look stellar when he was fooling opposing batters; the data backed up the eye test. Amongst all MLB changeups, his ranked in the Top 10 by tjStuff+, sitting right with Hayden Birdsong and Ryan Pepiot as the only starters on the list.
Another fascinating aspect of Davis’ changeup is how it interacts with the other pitches in his arsenal, most notably his slider and cutter.
Slider
Martin’s slider is his most utilized secondary against RHH, thanks to its fair amount of sweep he generates on the offering. He has a great feel for the pitch and consistently paints it down-and-away against righties.
The slider complements his changeup well due to their mirrored movement profiles. While the slider averages ~8” of sweep, his changeup averages ~13” of arm-side run, both with similar depth. When Martin tunnels these offerings well, determining which direction the ball is heading is a guessing game. Take this sequence against Aaron Judge as an example.
Earlier in this at bat, Davis located a changeup below Judge’s knees, where Judge took a mighty hack and whiffed over it.
Two pitches later, Martin placed his slider where he typically does, low and away, to get Judge out on strikes after a sword.
Looking at an overlay of the pitches, we can see how frustrating Martin is to face. Both pitches follow similar trajectories towards the plate, including overlapping late into their flight, only for them to veer in opposite directions. Judge would have likely connected on another changeup, but the slider was simply out of reach.
Cutter
Martin added a cutter this season, and it returned excellent results. It was his 4th most used pitch while simultaneously being his most valuable according to Baseball Savant Run Value (+5). It was also effective against both handedness, mostly driven by strong command.
Similar to his slider, Martin’s cutter pairs well with his changeup. Their similar velocity bands and release points make the pitches difficult to distinguish out of hand, but they have drastically different movement profiles. His cutter exhibits minimal arm-side movement and less vertical depth than his changeup.
This overlay of his cutter and changeup against LaMonte Wade Jr. illustrates how the pitches vary greatly from each other.
Growing Pains
Not everything was smooth sailing for Davis with the introduction of his kick changeup. It was effective against LHH, returning an exceptional +4 RV on 109 pitches, but he struggled immensely against RHH, posting a -6 RV on 66 pitches. Digging deeper into batted ball quality and contact metrics illustrates an opposite picture, with his changeup getting hit much harder and more often, by LHH.
In particular, his approach against LHH was inconsistent, as he left too many pitches hanging in the heart of the zone. Like any new pitch, getting a good feel for the pitch will take time, and that timeframe is typically extended following Tommy John surgery.
Looking Ahead to 2025
Davis Martin has a solid foundation to be an effective starter in MLB. He wields a 5-pitch mix, highlighted by a strong slider and seemingly elite changeup, which he elevates with mid-90s velocity and elite spin rates.
In my opinion, Martin’s 4-seamer is the crux of his arsenal. It was his most utilized pitch in 2024 and returned putrid results against both LHH and RHH. It registered -7 RV this season, and there are a handful of aspects that explain its ineffectiveness, including its uninteresting shape, his tendency to throw it in uncompetitive locations, and his telegraphed release point.
Martin’s cutter was his most productive pitch in 2024, and he displayed refined feel for the pitch despite introducing it this season. It plays off his kick change and slider well and provides a platoon-neutral option that he lacks. I would like to see him increase the usage of the offering in 2025, mostly leeching off of his 4-seam usage.
Conclusion
Player development is seldom linear, and Davis Martin is a perfect example of that. He worked with Bannister and Katz to learn a new pitch that reinvigorated his prospects as a starter seven seasons into his professional career. Kudos to Bannister and Katz leveraging their prior experiences to maximize Martin’s potential, and props to Martin for being open to redefining himself. His 2024 season showed a lot of promise, and he has the support and tools to make the necessary changes to succeed in 2025.
Thank you for reading!
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thought you were mostly just a stats guy but the writing here is tremendous. Excellent work TJ