Mariners Reliever Matt Brash Shut Down Indefinitely

The Seattle Mariners entered the 2024 season expecting to once again run out one of the deadliest bullpens in the game. Fast forward to now and they have done just that, ranking in the top ten of the league in almost all categories.

But they have had to do so without arguably their most lethal weapon. And they may be doing so for a long while.

Matt Brash was shut down early in spring training due to elbow inflammation. He seemed to originally avoid a major scare, working his way back since early March and as recently as last week was on the doorstep of a rehab assignment.

But last weekend, it was announced that Brash has been shut down indefinitely as he continues not to respond well in days after ramping up to full speed.

Brash is heading back to Dallas to meet with Dr. Keith Meister, and the Mariners have expressed that they are concerned.

While there is still the chance that Brash avoids another major scare after meeting with the doctors, this unfortunately has the feeling that it is headed for a worst-case scenario. That being Brash undergoing Tommy John Surgery, and as a result the Mariners being without him for all of 2024 and potentially a good portion of 2025 as well. 

In GM Justin Hollander’s media session in which he gave the update on the right-hander, he explained that Brash has been able to ramp his stuff all the way back up, including with his near 100 MPH fastball. The issue for Brash is not reaching the peak with his offerings, it is how his arm has responded the next day or days afterwards.

The day before Brash was tentatively scheduled to go out on a rehab assignment he threw in Seattle at T-Mobile Park. And Hollander relayed that Brash said after that sessions “every throw felt bad”.

That line feels like a gut punch.

The Mariners did not specify when exactly Brash’s meetings with the doctors would be, so for now there is just the hope that Brash can dodge another bullet.

Brash has been one of the best relievers in baseball ever since he was converted to a bullpen arm in the middle of 2022. Last year he ranked fourth among all relievers in fWAR (2.1) and third among all qualified relievers in K/9 (13.6) while posting a 3.06 ERA and a 2.26 FIP.

Along with his heater, he owns the nastiest sweeper in the game, looking like a wiffle ball out of his right-hand.

The way Seattle has managed to remain a top bullpen unit in the absence of Brash is thanks to a trio of arms.

One is Andres Munoz, who has also cemented himself as one of the game’s best bullpen arms, and has now been a constant at the back of the Mariners bullpen for the third consecutive year.

The second is Gabe Speier, who broke onto the scene a season ago with his incredible knack for throwing first pitch strikes and getting the opposition to chase his offerings. As a result, he now regularly throws in high leverage for the Mariners and held an 0.84 ERA before allowing two runs to the Astros this past weekend (now it only sits at 2.45). 

And finally Trent Thronton, who now can often be found in the bridge reliever role that Brash used to occupy when a starter gets removed in the middle of an inning, typically in the sixth or seventh. Thornton, like Brash, also works off of his sweeper, does not allow hard contact, and just over a month into the season has a 2.70 ERA and a 0.90 WHIP.

Ryne Stanek also throws in plenty of late game scenarios, but he hasn’t reached his peak form quite yet.

All of that, however, doesn’t account for the reliever with the firepower to replace Brash in the smoothest fashion. Gregory Santos has missed the first month of the season due to a lat injury. But he is progressing in the right direction and appears to be on a timetable to return in late May or early June.

Santos hurls a slider that gives opposing hitters nightmares. He posted a Run Value of 17 with that offering a season ago, which was even higher than the value of Brash’s sweeper (per Baseball Savant). He is also continuing to work on a sinker with an average velocity of 99 MPH that he had never thrown until last year. Santos put up a 3.39 ERA and a 2.65 FIP in 2023 while allowing just two home runs across 60 appearances.

The Mariners have turned undervalued relievers into stars over the last four seasons. They have never acquired a bullpen arm of this caliber to place into their system, showing just how highly they think of the former White Sox righty. Santos also has five years of club control.

So yes, there is a chance that Seattle will be without Brash for the year. But if that is the case, they are very well equipped to remain as one of the league’s toughest bullpens.