PEORIA, Ariz. – When Brandon Brennan was a Rule 5 Draft pick for the Mariners last season, that status came with some protection.

Unless the Mariners wanted to return Brennan to the Rockies, they needed to keep him on their Major League roster for the full season. And Seattle general manager Jerry Dipoto -- looking to add bullpen talent through every available avenue -- had no intention of losing Brennan, who pitched very well in the first half before dealing with some fatigue and injury issues after the All-Star break.

But with his Rule 5 situation expired, Brennan is in a different boat in 2020 and he knows it. Now the Mariners are free to option the 28-year-old right-hander down to the Minor Leagues without fear of losing him to another team, which means he’s on the proverbial roster “bubble” on a team with about 15 competitive relievers battling for eight spots on the Opening Day squad.

A good number of those spots appear sewn up by circumstances. Yoshihisa Hirano and Carl Edwards Jr., who threw a scoreless inning in Seattle's 7-3 loss on Sunday, signed as veteran free agents this offseason and are virtually assured spots to start the year. Dan Altavilla is out of Minor League options, so the Mariners have to keep him or expose him to other clubs through waivers.

Matt Magill, Sam Tuivailala and Erik Swanson pitched well enough in the second half last year to be penciled into plans, though all three have dealt with nagging injuries to start camp. And Yohan Ramirez, who allowed two runs on Sunday, is this year’s Rule 5 pickup and thus almost certainly makes the roster, given the club’s intrigue with his high-90s heat and nasty slider.

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That’s seven names already … and the club would like to keep a multi-inning reliever like Nestor Cortes, or even put rookie starter Justin Dunn in position to piggyback with Taijuan Walker if Walker isn't ready to throw more than 4-5 innings as he returns from two years of arm injuries.

Add in a number of promising prospects in camp and you might think the situation would be gnawing at Brennan, who is smart enough to do the math. But it turns out, Brennan is smart enough to also ignore the math, as well as the speculation.

“To be honest, at this point the only thing you can control is what you do on the field,” Brennan said. “If you want to break it all down and play GM, you’re going to hurt yourself a lot more than you’re going to benefit yourself.”

But surely he looks around the clubhouse and ponders the possibilities, no?

“For me, I don’t pay attention to any of it,” he said. “They already have a pretty good idea of who is going where to do what. Most organizations do. Obviously there are certain guys who are bubble guys every year, which is understandable. And if you’re one of them, the only thing you can do is go out on the field and show them what you can do.

“So at this point, I’m just hanging out with the guys, having a good time, getting back to baseball and then when the season comes around, we’ll see what happens. That’s really the only thing I can do.”

Brennan put his focus on refining his bread-and-butter changeup this winter, using Rapsodo feedback to find and maintain the most effective release point. And he worked out harder than ever to get physically stronger, knowing he’d worn down in his first big league season.

The changeup has been impressive so far this spring, looking like the pitch that helped him post a 2.05 ERA and .176 opponents' batting average over his first 21 appearances as a rookie. But those numbers jumped to 7.71 and .231 in his final 23 outings while splitting time on the disabled list.

Clearly he needs to be the first-half Brennan to land a roster berth, but he notes the best way to earn that spot is to keep a clear and positive frame of mind no matter what happens.

“Obviously, yes, I want to be in the big leagues right away,” he said. “When camp breaks, I want to be with this team, without a doubt, that is my goal. No way of getting around that. But you can’t control what Jerry and Scott [Servais] do. I have zero control of that. There’s no point in me even messing with it in my head. It’s a lot of wasted energy.”

Ironically, Brennan acknowledges that being a GM and helping put together the “giant puzzle” of a team sounds fascinating to him. But no, he’s not gunning for Dipoto’s job or any other front-office position.

“I’m definitely going to play until I literally can’t throw a ball anymore,” he said. “I don’t care how long that is. Until someone tells me I’m not allowed to come back, I’m playing.”