What is the upside of Mariners prospect Logan Gilbert?

While we are waiting for baseball to return, the Mariners best pitching prospect showed out this spring. This leads to the question, “what is the upside of Logan Gilbert“?

Fan of the Seattle Mariners should already know about Logan Gilbert. The 14th overall pick of the 2018 draft out of Stetson University, turned heads this spring after an incredibly successful initial foray into professional baseball.

In fact, Gilbert’s rise through the minor leagues was something this franchise hasn’t seen in a while. Gilbert pitched at 3 levels in 2019 (A, A+, AA) and more or less dominated each one. He finished the season with a 2.13 ERA, a 0.948 WHIP, 165 K’s, and just 33 walks in 135 innings. For you math experts at home, that comes out to an 11.0 K/9 and a 2.2 BB/9 rate. That is exceptional.

But minor league stats rarely tell the whole story, or even most of it for that matter. There is still the matter of the things numbers won’t tell you. In short, what kind of stuff does Gilbert currently possess? A cautious man would call it above-average stuff, but let’s break down his arsenal.

Gilbert gets value from his fastball, a critical factor in succeeding in the major leagues. It sits in the 92-95 range but he has touched 97 MPH. The pitch shows good life up in the zone and he can occasionally run the pitch in on righties. Most importantly, he throws the pitch for a strike and has plus command of the offering, setting up his other off-speed pitches to play up even more.

Gilbert has two legitimate breaking balls. The curveball is typically ahead of the slider, but both flash plus with frequency and are above-average offerings most nights. Gilbert’s final pitch is a changeup and it is the one that needs the most work. It is a bit firm at times, but Gilbert typically throws it with good arm speed and for strikes. It is a fringe-average offering right now, but shows good promise and won’t be left for dead by Seattle or Gilbert.

Gilbert has the size scouts dream of, cutting an imposing figure on the mound with his 6’6″, 230 lb frame, with long arms that make him appear closer to home plate than he is. The pitching motion is highlighted by a strong lower half which should help him maintain command and go deeper in ball games.

Gilbert’s profile falls short of an ace for me. In order to get there, he would need to sit more consistently in the 95-97 MPH range with the fastball and improve the changeup a full grade. If he can’t figure that out, he would need to improve his command even more so.

Gilbert does have that opportunity though, so we can’t completely discount that possibility. As things stand now, he should be a solid #3 starter who could eventually become a #1 starter, though his path to being a “true” ace is a bit of a stretch to expect.

As it stands right now, the ceiling for Gilbert may best be compared to Aaron Nola. Over the past 3 seasons, Nola has averaged 194 innings pitched, a 3.23 ERA, a 3.44 FIP, 212 strikeouts, and anywhere between a 3.9-10.2 bWAR.

It’s unlikely Gilbert will ever have a season like Nola’s 2018. Heck, it is unlikely Nola will have another season as he did in 2018. But Gilbert has every chance to be a 3.5-4.0 WAR pitcher on a regular basis, with the opportunity to reel off a couple of 6+ WAR seasons.

While that may not be what we typically assume an ace to be, it is pretty darn close and would likely land him as one of the 25 best starters in baseball. And for Mariners’ everywhere, that should be music to one’s ears.