The Angels Are Splinkering Around in the Lab

The Angels are in a rough place. With Mike Trout injured, Shohei Ohtani departed, and pitchers like Patrick Sandoval and Reid Detmers injured or struggling, it’s no surprise that they’re on pace for another 90-loss season despite a recent six-game winning streak. Their main source of their woes has been their long-struggling pitching staff, which this year has the third-worst ERA and walk rate in the majors. And while the Angels have taken extreme measures to add pitching depth to their farm system, the next generation of young pitchers in Anaheim aren’t exactly aces. This is to say that any short-term improvements to the staff will have to come from improvements to hurlers already on the big league roster. This year, they’re attempting to do just that by embracing the newest pitch to come into vogue: the splinker.

The splinker is still pretty new in the timeline of pitch design; its early adopters include Jhoan Duran and Paul Skenes. This sinker-splitter hybrid is difficult to classify because so few pitchers throw it, but such offerings generally sit in the same velocity band as four-seam fastballs while killing spin and lift in a manner similar to splitters and changeups. The end result can be downright nasty: Skenes has accumulated a +10 run value with his splinker across just nine starts, only a couple runs better than the first Angel to pick up the pitch, José Soriano.

Soriano’s journey to a major league rotation has been a wild one. As a teenager, he rose through the minors as an erratic flamethrower. Then, in 2020, the Pirates selected him in the Rule 5 draft, only to return him to the Angels in November of 2021 after he underwent Tommy John surgery twice in consecutive years. Despite pitching just 16 2/3 innings from 2020-22 across three levels of the minor leagues, none above Double-A, Soriano spent most of ’23 with the Angels as a middle reliever. He lived up to his reputation as a prospect, using his 99 mph fastball and lethal curve to strike out a dozen batters per nine innings. But he also walked five per nine, and his control issues put a hard ceiling on his role.

Soriano’s history with elbow injuries as well as a profile that played up in single-inning bursts out of the bullpen made it unlikely that he would ever be transitioned back to the rotation, yet that’s what the Angels decided to do with him in April. Now forced to stretch out to face the order multiple times, Soriano needed a pitch that could generate outs in the strike zone. His knuckle curve, which he threw a plurality of the time as a reliever, often missed well above or below the zone, while his four-seam fastball was knocked around to the tune of a .565 xSLG. In came the splinker.

Last year, Soriano played with both a sinker and splitter, but his splinker is a new, distinct offering. He’s added two inches of drop, making it behave more like an offspeed pitch than a fastball, even as it sits at 98 mph, just one tick slower than his four-seamer. He’s kept the more traditional splitter in his arsenal, too, but has slowed it down a bit and now only features it against lefties. Soriano’s reworked splinker is one of the most incomparable pitches in baseball, as even the most physics-defying sinkers fail to reach the same numbers in both velocity and drop.

Centering his arsenal around the splinker has completely transformed Soriano’s batted ball profile. In his bullpen days, he relied heavily on whiffs, often losing hitters if they didn’t chase his curveball outside the zone. This year, he’s increased his groundball rate by 9.1 points, trailing only Framber Valdez and Cristopher Sánchez among starters with at least 70 innings. The splinker has been the primary contributor to this increase, sporting by far the highest groundball rate in his arsenal. Even more, he ranks second in line drive avoidance, completely neutralizing the quality of contact against him.

Soriano’s splinker-fueled adjustments have made his transition to the rotation incredibly smooth, and he’s worked far more efficiently than you’d expect from someone who perennially ran a double-digit walk rate. He’s landed his splinker in the zone with far more consistency than any other pitch type he’s ever thrown, inducing early-count swings that get pounded into the ground. Soriano now ranks in the 79th percentile in pitches per batter faced, allowing him to average nearly six innings per start despite being on a strict pitch count, and although he’s never thrown 100 pitches in a game and is averaging just 85, he’s pitched into the eighth inning twice. With an ERA and FIP below 3.50 in his dozen starts, Soriano’s new weapon has turned him into a mid-rotation arm.

Soriano isn’t the only young Angels pitcher who’s been bit by the splinker bug; it’s also spread to rookie reliever Ben Joyce. Over the past two years, Joyce has gone from the hardest-throwing pitcher in college baseball to the hardest-throwing pitcher in the majors, with his 101.5 mph four-seamer beating out the likes of Skenes, Duran, and Mason Miller (another reliever who’s tried out the splinker). When you have a triple-digit heater coming from a low release angle, it’s hard to imagine needing to throw anything else. Indeed, in his 2023 cup of coffee, Joyce threw fastballs 80% of the time, with the rest of his pitches being sliders. But Joyce decided to add to his repertoire, picking up a new grip from veteran teammate Hunter Strickland, who himself has reinvented the shape of his sinker. Joyce threw his splinker for the first time on June 11, his third outing after being recalled from Double-A. Since then, his new toy has been his most used pitch.

Typically, pitchers need months or even years to get comfortable throwing new pitches in games, taking their time to refine them on the backfields before deploying them against big league hitters. Joyce, on the other hand, went from throwing it for the first time to making it his primary pitch in just a matter of weeks. And the results have followed his increased splinker usage. We have only 11 innings of data to work with, so we have to keep the small sample size in mind here, but the 33 batted balls against him this season have averaged a negative launch angle, putting him in the company of very few other pitchers (including Soriano). He’s induced five times as many groundballs as fly balls, compared to a roughly even distribution in the minors. And while it’s hard to compare Joyce’s splinker to other pitches, the models have certainly bought in, with PitchingBot assigning it a full double-plus grade.

This is probably the nastiest sinker/splitter/splinker that Ben Joyce has thrown since he incorporated into his arsenal earlier this month.

99.9 mph with 16.1 inches of run. pic.twitter.com/KPeuqER6GS

— Brent Maguire (@bmags94) June 25, 2024

Joyce’s splinker isn’t just effective in a vacuum; it’s especially useful when looking in the context of his arsenal. His four-seamer is excellent thanks to its velocity and vertical approach angle, but it doesn’t get the same riding action as other fastballs due to his low arm slot. While hitters who can handle premium velocity may be able to adjust to a heater without elite carry, it certainly becomes much more difficult when Joyce comes at them with a pitch thrown nearly as hard but drops an entire foot more. Furthermore, his splinker has seam-shifted wake properties that move its spin axis slightly more horizontally, almost perfectly mirroring that of his slider. In other words, while Joyce’s splinker puts up big run value numbers on its own (already leading his arsenal), it can also make his other pitches more effective.

It’s likely that we’ll soon see more and more pitchers throw the splinker as the few who currently do find more and more success with it. Over time, teams will learn more about what makes these pitches successful and train their pitchers accordingly, while hitters will do their best to adjust – continuing a never-ending cycle of evolution in the sport. The Angels have been far behind the curve on countless other developments in baseball, but the splinker has been one area where they’re among the first to reap the rewards.