SEATTLE -- With less than one month until the Trade Deadline, the Mariners made a big move on Saturday, adding a high-leverage bullpen arm that touches 100 mph with a wipeout slider that has recently reached the low-90s.

No, they didn’t make a splashy blockbuster deal. This arm is a familiar face -- Matt Brash is back in the big leagues.

Two months after a Minor League option and a transition from a starting to relief role, Seattle’s No. 3-ranked prospect and MLB Pipeline’s No. 92 overall returned to T-Mobile Park, eager to contribute in a new capacity. And he made an immediate impact with a scoreless inning in Saturday night's tense, 2-1 win, throwing 25 pitches, striking out two and dialing his fastball up to 99.7 mph. Brash's heater averaged 98.7 mph, way up from the 95.9 mph he had pitching in the rotation.

“It’s definitely exciting to be back and join this group when they're playing so well right now,” Brash said. “I'm just going to try to help this team win. It's what I've always wanted to do.”

So, why did the Mariners decide now was the opportune time for Brash?

There is an obvious need in the bullpen after Ken Giles suffered a shoulder injury in Friday’s win and Erik Swanson was placed on the paternity list after the birth of his daughter. Brash’s return was part of eight roster moves that also included George Kirby being optioned to Triple-A Tacoma in a workload-management decision to better govern his innings as they eye his contributions in the second half.

But back to Brash -- the Mariners also believe that he’s adjusted positively to the transition, and more chiefly, better harnessed the strike zone.

Brash will be injected for leverage pockets, like Saturday, though the Mariners will likely ease him in with opportunities to begin a clean inning rather than with runners on, similarly to how they previously handled Andrés Muñoz, who is now regularly deployed with traffic. Muñoz followed Brash on Saturday and looked arguably more electric, striking out two. It was a preview for what could be a high-caliber tandem for manager Scott Servais.

"Matt did not back off," Servais said. "Matt is a really good competitor. He is. I asked him when he came out of the game tonight, 'A little bit more adrenaline out of the bullpen?' He said, 'Oh yeah. A little bit.' And we're going to see it with his stuff, I think. But he's learning. He'll continue to get plenty of opportunities. It's a pretty good duo, young kids, coming out with that kind of stuff with him and Muñoz."

The Mariners will be cognizant that everything about Brash’s relief role is new, having developed as a starter. At first, his adjustment was about learning a new routine and arm care. 

“It’s a different process, for sure,” Brash explained. “I always wondered how I’d bounce back in this role because I've never done it before. Starting off, you get pretty sore the day after. But going in and for the one inning has been solid, and I've been feeling really good. It’s nice to know that I can bounce back.”

How about mentally adjusting to knowing he could pitch every day?

“Just staying locked in near the later parts of the game,” Brash said. “Starting, obviously, you're pitching the first inning, and then other days, you know you're off, so it's just being ready every day and staying locked in throughout the game and kind of just being ready because you never know when your name gets called. It kind of took me a while to kind of chill out for the game and then lock it in as the game gets going.”

And the lifting and workout routines?

“You just kind of have to pick and choose your days,” Brash added. “Starting, you had your set five-day routine. You just follow it every day. Now, depending on days I pitch, I'll lift, or if I know I'm off a day after pitching, like back-to-back, then I'll have that day. It's just kind of picking and choosing when to get your lifts in and what you do for your throwing program that day depends what days you're going to throw and that kind of thing.”

Brash had a 13.9% walk rate in 22 outings for Triple-A Tacoma, just a hair under the 17.9% he had in five big league starts, the highest in the Majors at the time he was sent down. Yet his numbers at Tacoma were exacerbated by a few of his earlier outings, as he’s walked only three of the past 46 batters he’s faced. Overall, Brash has held hitters to a .207/.311/.380 (.692 OPS) slash line in 26 innings, with a 3.46 ERA. In the Majors, he had a 7.65 ERA in 20 innings. 

When the Mariners made the decision, it seemed like an aggressive pivot for one of the top young arms in their pitching-heavy pipeline. They’ve since said that the move is not necessarily a permanent one. Brash’s stuff is conducive to high-leverage relief innings, and their reasoning was opting for how they can be at their best for 2022. Brash has since embraced the transition. 

“I'm just here to help the team right now in the 'pen,” Brash said. “I'm not quite sure of my [bullpen] role, but however I can help.”