BY ALL MEASURES,

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But for all of the benefits of adding new options to an arsenal, only the lucky few have done so without feeling defeated by a particular pitch.

Gilbert, a 27-year-old right-handed All-Star for the Seattle Mariners and proud member of the five-pitch club, exemplifies how the mix of pitches in a starter’s repertoire is always evolving, even when it comes to the game’s best. In 2021, his rookie season, Gilbert threw eight different types of pitches: four- and two-seam fastballs, a standard and knuckle curve, a slider, a cutter, a changeup and a splitter. He discarded the splitter, cutter and standard curve in his second season, only to re-add a better version of the splitter in 2023 because nothing exasperated him quite like the changeup has throughout his career.

“That’s why I got rid of it,” Gilbert said during spring training. “Except recently I threw one in catch play and kind of felt good, so … I need to stop”

Unlike pitchers who will add and subtract offerings during the middle of the season, Gilbert believes the winter and six weeks of spring training are the time to lock in pitches for the season ahead. After reintroducing the traditional curve and cutter in 2024, he settled on a more limited arsenal for 2025, leaning heavily on his four-seamer, splitter and slider while feathering in curves and throwing a few two-seamers each game.

“I’m naturally black and white, logical, scientific, and that’s kind of how I create pitches. But that’s offseason work,” Gilbert said. “When you’re on the mound, when you’re in the game, you kind of switch back to be able to [be] the artist, so to speak. I work with [Mariners mental skills coach Adam Bernero] a lot on that. It’s about feel. It’s about letting go. It’s about things that you can’t quantify that kind of sound made up, but that’s what makes me a really good pitcher. Probably other guys, too. It’s not that when you’re out there you’re thinking about how do I throw this sweeper with as much break as possible. That’s behind the scenes. And the good guys, I feel like, can switch back and forth between that.

“You start leaning into this stuff — like the process, not the result — and letting go and getting rid of expectations, and stuff like that actually makes you a better pitcher. It sounds so great, but in practice it’s such a hard thing to do. It’s great until somebody gets a double and it’s even harder, but you have to commit to it beforehand and stay committed to it.”

Sticking with something that can potentially lead to suboptimal results while being perfected is a much less difficult proposition for an established major league star than it is for a young pitcher trying to climb an organizational ladder while optimizing his pitch mix for future performance.

When Minnesota Twins starter Joe Ryan was drafted by Tampa Bay in 2018, he asked a scout what allowed Brendan McKay, the Rays’ first-round pick the year before, to move through the organization so quickly. Simple, Ryan was told: McKay’s fastball was so good that lower-level hitters couldn’t touch it, so McKay just carved up lineups with it. That sounded good to Ryan. Hitters struggled with his deceptive four-seamer, thrown from a relatively low slot and with well-above-average backspin. He threw it about 90% of the time. But the Rays’ farm director at the time, Mitch Lukevics, warned Ryan that he would need a greater repertoire as he ascended in the organization, so in his next start, Ryan threw a curveball that got obliterated for a three-run home run. His High-A pitching coach, Doc Watson, told Ryan he should have a new game plan: “Throw f—ing heaters.”

Ryan kept putting off the curveball as he learned other pitches. He was told he needed a changeup to move to Double-A, and he developed one within 10 days. He picked up a sweeper, ditched it at the behest of the Rays and unleashed it again after he was traded to Minnesota. He scrapped the changeup for a splitter in 2023, and it’s now his second-best pitch. The curveball remains his white whale.

“But I threw one the other day and it was the best curveball I’ve ever thrown,” Ryan said. “I’m like, all right, maybe I can do this. But if you have a sweeper, split, short slider that’s hard, sinker, four-seam — I don’t know where the curve works in the equation as much. If you … can just sit on one pitch the whole time, it’s going to be a really tough game. But if you can go in there and just mix the whole time and you have good s—, it’s going to be a really tough day for them.”

FOR MORE THAN a decade, Kenta Maeda could not throw a split-fingered fastball. Splitters are a trademark for most of the best Japanese pitchers, but when Maeda tried to throw one, it didn’t tumble. To hitters, it looked like a batting-practice fastball.

Maeda sought advice from around the game on how to properly throw a splitter. He asked Hideo Nomo, the godfather of modern Japanese pitching, and Masahiro Tanaka, whose splitter led him to a pair of All-Star Games with the New York Yankees. Maeda never worried too much about his lack of a splitter because his circle changeup was plenty good.

In 2018, his third year with the Los Angeles Dodgers, he lost the feel for his change and started to scramble. Without a change, he needed a split. “It was time for me to maneuver that pitch,” said Maeda, the 36-year-old Detroit Tigers right-hander who almost always has a ball in his hand when he’s sitting on the bench. Most pitchers are tinkerers by trade, fiddling with grips and pressures, trying to find something that’s comfortable. Rather than copy his countrymen, who jam the ball between their index and middle fingers to throw a splitter, Maeda conceived of a splitter with some characteristics from his circle change. He put his index and middle fingers together, splitting the ring finger.

“Then I started playing with that pitch during catch play,” Maeda said, “and here we are.”

Six years later, Maeda still throws the split. It’s the sort of thing that gives Skubal hope. He saw how a new pitch can be an immediate success this winter, when San Francisco Giants left-hander Robbie Ray texted asking Skubal how he gripped his changeup. Skubal sent photos and video to explain the pitch to Ray, a reflection of the pitching fraternity in which trade secrets are shared regularly, even among opponents.

Ray cottoned to the changeup and is throwing it nearly 13% of the time this season, the highest percentage since his rookie season in 2014. Ray’s success with it is a reminder of how difficult learning a new pitch can be, because a far more accomplished pitcher has spent nearly two decades trying to find a change upon which he can rely. For the entirety of his 18-year career, Kershaw has entered spring training in search of a usable changeup, only to throw it a dozen or so times a year. Sometimes a pitch isn’t meant to be.

Skubal isn’t there yet with his slider. Still, he’s a competitor, a perfectionist and a realist, so if he couldn’t land Kershaw’s slider, he figured, maybe an alternative would work. During his interactions with Ray, Skubal asked about his slider, which helped Ray capture the AL Cy Young in 2021.

“He showed me his grip, showed me his cues, everything,” Skubal said. “I tried it. I’m like, dude, it doesn’t work. But it works for him. I love his slider. It’s a really good pitch. It didn’t work out in my favor, worked out in his, but maybe it’ll work again. I’ll revisit it.”