The reasons why Seattle Mariners fans love Logan Gilbert go beyond the basic fact that he’s one of the best pitchers the franchise has ever produced. To wit, there’s also how he just keeps finding ways to get better.

The story of Gilbert’s career is generally one of forward progress, to a point where he entered this season off a 2024 season that almost seems impossible to improve on. Gilbert ended up leading MLB with 208.2 innings and a 0.887 WHIP.

His ’24 dominance was driven by several changes, including a basically equal partnership between his fastball and slider. He also threw the former harder as 2024 went along. Come September, the 6-foot-6, 215-pound righty was sitting at 97.7 mph and touching 100 mph.

Yet here we are in 2025, wherein Gilbert is again threatening new personal bests with a 0.878 WHIP, a 2.63 ERA and a rate of 13.5 strikeouts per nine innings. And it all stems from another new trick: placing more trust in a pitch nobody can hit.

Calling Logan Gilbert’s splitter ‘unhittable’ is not an exaggeration

We’re talking about Gilbert’s split-finger fastball, which instantly has a case as the best pitch in MLB today based on its key statistics. Here’s where it ranks among all pitches that have been thrown at least 500 times since the start of the 2024 season:

The one pitch that compares with Gilbert’s splitter in these categories is actually another splitter, namely the one thrown by New York Yankees reliever Fernando Cruz. And yet, even his (admittedly also excellent) splitter hasn’t been as dominant as Gilbert’s so far in 2025.

The 27-year-old has used his splitter 113 times so far this season — effectively doubling its usage from 13.4 percent to 24.0 percent — and these have yielded a 50.0 whiff percentage as well as a 1-for-32 line with 21 strikeouts. The one hit was a mere single, and we must give credit for Toronto Blue Jays catcher Alejandro Kirk for getting it fair and square with a 97.1 mph line drive to left field.

Yet as helpful as statistics are, any “Best Pitch in Baseball” conversation must inevitably stop dancing around the question people really care about: Does it look any good?

To this end, our vote is a hard yes. Gilbert’s splitter indeed has all the necessary aesthetics of an unhittable pitch, especially in the sense that it behaves as if it’s allergic to wood:

The splitter is an inherently low-spin pitch, but Gilbert takes it to an extreme. He’s getting an average of 762 revolutions per minute on his splitter, the second-lowest of any pitch this year after the splitter thrown by Los Angeles Dodgers rookie Roki Sasaki.

This is sort of a double-edged sword, as Gilbert explained to Tim Booth of The Seattle Times earlier this month:

This volatility does come with real risks. Every time Gilbert throws the splitter with a man on base, he’s risking a wild pitch. And if a splitter catches too much of the strike zone, its low spin won’t necessarily be an asset.

At least for now, though, these are purely abstract threats. Neither of the two wild pitches Gilbert has this season came on splitters, and the pitch certainly isn’t getting hit hard.