Mariners’ Matt Brash’s slider may be ‘best pitch’ in MLB history

You don’t need to be a pitching expert to know that Mariners relief pitcher Matt Brash has nasty stuff on the mound. But if you ask a pitching expert just how nasty Brash is, you’re probably going to develop an even bigger appreciation for what he can do.

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Brash was a weapon out of the Mariners’ bullpen down the stretch last year, using his fastball in the upper 90s and a hard slider straight out of a cartoon to make it through 35 scoreless appearances over his final 37 games, including the postseason. There are high hopes that he can build on that in 2023, even after he pitches for Team Canada in the World Baseball Classic next month.

To get an idea of what makes the 24-year-old Brash’s arm stand out as especially electric, Seattle Sports’ Wyman and Bob talked to Driveline Baseball director of pitching Chris Langin on Monday. Driveline, known as a premier destination for data-driven baseball training, is a popular spot for big leaguers during the offseason, with players from all over MLB – not just locally – flocking to their facilities in Kent, Wash., and Scottsdale, Ariz.

That’s to say Langin has seen a lot of impressive athletes, making what he had to say about one of Brash’s pitches all the more exciting.

“I think you could pretty realistically say his slider is maybe the best pitch in terms of pitch movement and velocity in major league history,” Langin said of Brash. “I actually think it’s, like, that absurd how good the stuff of that pitch is.”

And that’s not all.

“The curveball is obviously pretty darn good, too. It’s got a little more depth so it can kind of be another option for left-handed hitters.”

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Brash began the 2022 season as the final starter in the Mariners’ rotation, but despite flashes of dominance he struggled with command was optioned to Triple-A to convert to a relief role. He was a different pitcher when he returned to Seattle’s active roster, posting a 2.35 ERA and 43 strikeouts to 16 walks over 30 2/3 innings out of the bullpen.

Remember the name: Matt Brash. pic.twitter.com/tO8z0xsffk

— MLB (@MLB) April 12, 2022

The next step for Brash, according to Langin, is finding one more reliable option that can bridge the gap between his fastball and breaking balls. The reason: hitters have shown they’ll lay off Brash’s slider and curveball knowing their best chance for success is to sit on a fastball.

“The fastball, in my estimation, at least the biggest thing it has going for it is it’s just thrown extremely hard, but the the movement profile on it wasn’t necessarily great so it was difficult without elite command – which he just doesn’t have, and that’s OK – to really get results as a starter with the pitch, and then even out of the bullpen,” Langin said. “Really, his results were a lot better when he went to those breaking pitches. So the No. 1 thing was really getting him something that can kind of merge that gap between (the fastball and) this disgusting slider that guys are going to be kind of resistant to swinging the bat at.

“His stuff is really just too nasty to be reliant on guys kind of standing there holding the bat on their shoulder. Really, when he started, guys just didn’t swing at anything, whether it was in the zone, out of the zone, so they really made him work to land those breaking balls. Those pitches can honestly be pretty difficult to command, and then when he went to a fastball, it really doesn’t have the movement profile where you can just kind of throw it down the middle and get away with it.”

The answer could be a cutter, a pitch that pretty much is a combination of a fastball and a slider – not usually thrown as hard as a fastball, and not with as much break as a slider.

“So that cutter was kind of the big thing development-wise that he’s been working on… and really, it’s kind of the pitch that is right in the middle of those other two pitches where there’s fastball, a breaking ball with some incredible movement that’s mainly swing and miss,” Langin said. “He just needs something in between to kind of basically force them to swing the bat at something that’s not a fastball, that’s really the main purpose of it.”

The cutter has taken some time this offseason to come together, in part for a reason that makes his slider so devastating.

“Brash has very unusual fingers,” Langin said, “so finding a pitch grip for him, I mean, it was kind of difficult because the way he grips the ball is just so niche compared to every single other player that I’ve worked with so that took a decent amount of time. And to be frank, the first day didn’t go that well… He couldn’t find a grip that he liked, and then he came back two days later, basically during his assessment and that’s basically where we saw, ‘Hey, you threw about 15 of these and 11 of them are acceptable, two of them are good.’ And at that point, you kind of just keep hammering it down for the rest of the offseason and he gets familiar with what the pitch is. The purpose of the pitch is not meant to strike out guys like his slider, necessarily, and he’s able then to lock in the movement a bit better throughout that time.”

Don’t think for a second that comment about Brash’s fingers wasn’t followed up on, by the way. Co-host Bob Stelton pried a bit more into it, and Langin did his best to describe why they’re such an asset without a visual example.

“His middle finger, he can hook the ball, like… the only guys I can think of is maybe Alex Cobb with the Giants and Marcus Stroman (of the Cubs). I don’t even know really how to explain it but (how) he can grip the ball, I think it’s why he spins it’s so darn well and just applies force to the ball forever – and the more I think about it, the more difficult it’s going to be to be able to describe over the radio,” Langin said with a laugh. “He can do things with that middle finger that probably explains why he can throw a slider like he can.”

Langin provided insight on much more during the interview, which you can listen to in the podcast player below.

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