Alternate title: The pursuit of “aggressive joy”
As always, I’m a day late and a dollar short. Grant Brisbee has beat me to the Kyle Harrison analysis. A reminder that awkward pubescent 14 year olds run the same 100 meters as Sha’Carri Richardson does — the difference is one competes for gold medals in Olympic arenas, the other on dusty school lots for the Presidential Physical Fitness Award.
Maybe someday… but today, I’ll just labor on, comforted that my analysis of Kyle Harrison’s pitch mix will at least be free.
The truth is an in-depth analysis to diagnose Harrison’s ills isn’t really needed. No Major League Baseball starter relies on their four-seam fastball as much as the young Giants southpaw (58% pitch usage), and even though it accrued a 7 run value (0.6 RV/100), the pitch didn’t prove to be the vehicle Harrison needs it to be. For most fastball throwers, a myriad of problems find their origin in velocity. The heat needs to be hot. We’re living in a Vin Diesel world: fastballs need to be faster and more furious than ever.
Harrison has the benefit of a more deceptive delivery than most, giving the appearance of zip that a typical 92 MPH four-seam wouldn’t have. But even if velocity is about perception, any lost ticks on the speedometer matter. In his rookie season, Harrison’s average fastball came in at 93.6 MPH; though over his first couple games, the average clocked in around 94.5 MPH. In 2024, the overall average MPH dropped to 92.5.
A ostensibly minor decline that doesn’t register on a graph detailing a broad spectrum of pitch-type speeds — but focus on the pitch type, mess around with the y-axis, and you have something that captures the precipitous drop that Harrison’s lost MPH represents.
The average spin-rate matched that velo decline, giving the pitch less of a rising action and more of a horizontal tail to his armside. Some lost action compounded by the fact that Harrison wasn’t the new shiny toy freshly unboxed. The plastic was off, and the wear-and-tear, the depreciation, kicked-in immediately. Hitters had more data, some prior, on-hand experience going into their confrontations. They were more comfortable against Harrison’s mechanics, better at picking up pitches out of his hand. Harrison didn’t do himself any favors either. He struggled to throw first pitch strikes, forfeiting count leverage to opponents early and often. They embraced the gift, swung more, made contact in the zone more, and chased less. Opponents’ batting average jumped from .179 in 2023 to .249, while their slugging rose from .385 to .425. The pitch induced more ground balls, but the average exit velocity and higher hard-hit rate increased. The overall batting average of balls in play rose from .236 to. 308.
There’s an abundance of differences between Kyle Harrison and Justin Verlander — but the most pertinent difference here is that the lefty is basically two decades younger than the veteran. The lower velocity for Harrison doesn’t presage more decline like it does for Verlander, nor do the injuries to his ankle and shoulder necessarily mean more will come. Brisbee started his article with a helpful framing: Harrison is the age of most prospects, imagine what he’d have done in double-A last year. Though he debuted two seasons ago, he only started seven games and threw 34.2 innings in 2023. J.P. Martinez pointed out in a recent interview that there are only a handful of 22-23 year olds pitching in the Majors, and even fewer matched Harrison’s results. Excitement should still abound for the kid.
So I hesitate to officially proclaim the four-seam as Harrison’s problematic pitch. Here I am, again, undermining my own terminology, confined by my own confines. The four-seam wasn’t at its best in 2024, but similar to Jordan Hicks, those problems were not necessarily found in the pitch itself but the circumstances of its delivery, like nagging injuries, and the stress of the early season workload that were beyond Harrison’s control. And for all its faults, the four-seam also kept Harrison competitive. I think Brisbee is absolutely right when he says that Harrison can be, and has been, a serviceable starter at the back-end of a rotation purely on the merits of his four-seam. What prevents him from filling a more elevated rotation role is his secondary pitches. I think it’s fair to say that the fans and front office alike need to see some forward bounds from Harrison in the 2025 season.
Progress has already been made. Last February, Harrison’s problematic pitch was his slurve. A dynamic follow-up punch to his fastball, the pitch in theory should be something of a finisher, a broom that sweeps across the zone, eliciting a desperate reach, and cleans off the plate for the next batter. Instead lefties feasted on it during Harrison’s abbreviated season, leaving him flummoxed against a hand he typically dominated.
Hark, tho! Rejoice! The slurve improved greatly in 2024. Lefties’ batting average dropped, their slugging fell from .900 (a small sample size inflated by two homers, but still) to .367. The swing-and-miss rate shot up from 9.5% to 33.3%. All groovy on the lefthand front.
The problem though — and this is probably a side effect of Harrison’s fastball woes — was that right handed hitters improved against the breaking ball in many of the areas lefties struggled in. The slurve just isn’t a standalone pitch against righties as it is against lefties. Rather than crowding the hitter or getting them to reach, the offering develops out in the open in front of right-handed hitters. The break can steal a strike on the outside corner …
but often it floats out into the “no-fly” zone over the plate.
It needs to be able to cloak itself in the rise of the four-seam. A slower fastball with less verticality and command had a negative trickle-down effect on the slurve, as well as Harrison’s newest supporting pitch: the change-up.
Harrion’s use of the change-up rose from around 11% in 2023 to 20% in 2024. Its development will be a key part of Harrison’s effectiveness against right-handers — and considering its -6 Run Value (-1.4 RV/100), the pitch needs to develop.
Another look, another speed, another shape — a third pitch is absolutely necessary for any starter trying to work deeper into games. An offspeed protects and enhances Harrison’s better offerings. The pitch has above average horizontal movement away from righties which will give the opposite break of the slurve more life. Similarly, keeping the offspeed down will help increase the play of the fastball up. A bonus is it can help improve Harrison’s dismal ground ball rate.
Sound theoretically, but so far practically, the change-up is still a work-in-progress. The tinkering is evident in how much his arm angle has changed over his brief career. His command is more-than-a-little all over the place, his grouping far from the tight geode of someone like Webb’s at the bottom of the strike zone.
But let’s zoom out for a second. A lot of the qualities that are hard to instill into a player, but are key to the success of a big leaguer, appear to be innate in Harrison. J.P. Martinez and Andrew Baggarly sang his praises discussing Harrison’s ability to keep the Giants in games when operating without his best stuff. That is pitching, and many guys can’t do it. They collapse, come apart at the seams, if their bread-and-butter isn’t doing what they want it to do.
For Martinez, Harrison needs to maintain that natural grit in 2025…and also lighten up a bit. In his eyes, an “aggressive joy” that Harrison pitched with in the minors was absent last season, drowned out a bit by the difficulties and stress of trying to establish last season.
Advice from a coach you wouldn’t necessarily expect to hear at this level, but I appreciate the sentiment. It’s a good reminder that pitching is not just about pitch-types, it’s about presence. Being Dave Stewart and his death ray glare helps; as does the goofy antics of a wiry Mark Fidrych, or the hectic aura of “awesomeness” (obnoxiousness, for some) Brian Wilson brought up to the mound with him.
How will Harrison manifest “aggressive joy” in 2025? A stringy mustache? An eye-patch? An uneasy grin during his delivery? Perhaps something a little more more subtle, like a new mantra on the mound to put things in perspective: Pitching is letting go…pitching is greater than the sum of pitches…pitching is a feeling…
