Coming into spring training, it wasn’t hard to make a good guess at what the Seattle Mariners’ bullpen would be heading into the season.

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If you did the math, looked at who was returning, the minor-league option situation and specific needs, the picture was clear. Barring injury, there was maybe one spot open. The bullpen all but complete, and a bullpen drawing high marks from the projections.

Oh, how quickly things can change.

Less than a week into full-squad action in Arizona, two-thirds of the back end of the bullpen landed on the shelf due to soreness after early bullpen sessions.

The good news: Gregory Santos appears to be on the mend.

The bad news: the uncertainty on Matt Brash’s situation, with updates being pushed further and further out.

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There should indeed be concern about Brash’s injury as he was set to be a vital part of the Mariners’ bullpen in 2024. It is looking more and more likely another bullpen spot will be open at the beginning of the season, and a few of the competitors – ones that are lesser known but fall into the “bucket” of pitchers who have stuff that perhaps with a tweak or a nudge from the Mariners pitching staff/lab could turn potential into needed production – had strong first outings the last two days.

“(Jackson) Kowar was outstanding as was (Collin) Snider,” manager Scott Servais said following the Mariners’ 9-7 Cactus League loss to the Royals on Wednesday afternoon (box score here). “Some good signs there obviously.”

Kowar, acquired from the Braves in the trade involving Jarred Kelenic, Marco Gonzales and Evan White, had a 1-2-3 third inning and fanned one while facing his former team, the Royals. Snider, also a former Royal, needed just seven pitches to get through the sixth.

“The are very different pitchers,” Servais said. “Kowar, it’s a little bit bigger fastball, you will see it up to 98 mph, outstanding changeup. The biggest thing with him is he’s got to get strike 1. He did it today. Snider threw seven pitches and they are all strikes.”

On Tuesday, it was Carlos Vargas, part of of the return from Arizona in the Eugenio Suárez, who impressed.

“He threw the ball really good,” Servais said of the one-inning outing. “The fastball is unique. It’s cutting, it’s sinking. His go-to pitch is the slider. Even his misses were very close. It’s a good sign first time out there.”

Vargas comes to the Mariners as a 24 year old with very good stuff but command issues, having walked 97 batters in 188 2/3 innings in the minors. The four-seam fastball sat at 99 mph last year but got hit at a .400 average in his five big league appearances. That fastball did not make an appearance against the Giants in Scottsdale on Tuesday. Rather, he utilized a three-pitch mix – two-seam fastball, cutter and slider – to good success.

“I was trying to attack the strike zone,” Vargas said through interpreter Freddy Llanos. “I have a lot more confidence in my pitches and it has been a lot of fun.”

The cutter is relatively new, with Vargas deciding after 2022 he needed to find another pitch to get hitters out. The slider has been his baby.

“The slider is something I have always worked on,” he said with a smile. “It’s one of those pitches that I am proud of. I feel I can throw it in any situation and get the results.”

While he did not hit the upper 90s Tuesday, all three pitches had a ton of movement and generated some silly swings from the lefty he faced. The tweaks that the Mariners have made with him so far have been simple, according to Vargas.

“Just throw the ball in the middle and attack, attack, attack,” he said.

Words and results Servais no doubt is happy to hear and see.

“They are buying into the program, they’re getting great results, and we are going to need them,” he said. “These guys have great arms and we are going to be seeing them throughout the season.”

Seattle Mariners bullpen update: RHP Gregory Santos

News on Santos is good. The 24-year-old right-hander played catch Tuesday for the first time since being shut down with lat soreness. The session went well with Servais calling the report “awesome,” and that the trainer who caught him said he wouldn’t catch him again. Rather, he would have a bullpen catcher do it. In other words, he was throwing hard.

Santos was acquired earlier this month in a trade with the Chicago White Sox after an impressive 2023 campaign.

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