5 Bullpen Arms Mariners Should Target Before the Deadline Market Explodes

Seattle’s deadline bullpen search should be practical, not desperate.

Jun 1, 2026; Anaheim, California, USA; Colorado Rockies pitcher Antonio Senzatela (49) celebrates after earning a win in the ninth inning against the Los Angeles Angels at Angel Stadium. Mandatory Credit: Jayne Kamin-Oncea-Imagn Images | Jayne Kamin-Oncea-Imagn Images

If the Mariners are going to move away from Andrés Muñoz as their closer, it would take a collapse hitherto undreamt of.

And since that’s not where we are, this bullpen conversation should probably start in a more honest place. Seattle doesn’t need to go hunting for a new closer. Nor do they strike us as a team ready to unload even more prospect capital.

But they definitely still need help. They need someone who can keep Matt Brash from being the emergency button once he’s healthy again. And at the same time, they shouldn’t act desperate or throw some kind of hail mary. 

So we don’t expect Seattle to walk into the deadline and throw a bag at the biggest name available. We already saw this movie last year with Jhoan Duran. The Mariners were interested, but the price was massive, and Seattle wasn’t ready to treat a reliever like the final boss of the trade deadline.

The Mariners should be shopping in a more realistic aisle. But, hopefully with more pedigree than Caleb Ferguson. So here are five names worth watching.

Mariners Should Target Bullpen Help Without Paying Closer Prices

JT Brubaker - San Francisco Giants

JT Brubaker would give the Mariners the length they need. Especially if all six starters stay on the roster through the trade deadline.

He’s not going to excite the fanbase much. But that’s not the kind of addition he’d be. He has starting experience, he can work as a multi-inning reliever and he fits the role Seattle seems to need, like, yesterday. 

The Mariners’ rotation obviously has enough talent to carry them, but the path from starter to Muñoz has been shaky. 

Brubaker has done enough to fit that lane, posting a 3.18 ERA with 25 strikeouts across 34 innings in 23 games. 

Pete Fairbanks - Miami Marlins

This one is kind of weird and uncomfortable. But hey, maybe a change of scenery could work. The surface numbers are pretty bad. There is no need to dress that up. Fairbanks has a 7.00 ERA with seven saves and 25 strikeouts across 18 innings in 20 games. He hasn’t looked like himself, nor the clean late-inning answer contenders usually want to buy, and the injury history makes the whole thing even less tidy.

But this is also why he belongs in the conversation. If Fairbanks were cruising through the season with a sub-2.00 ERA and his usual late-inning dominance, the Marlins would probably be more reluctant to move him. The price would also be uncomfortable. Maybe it still is, because Miami loves the guy and he has an option for next season.

Fairbanks still has late-inning stuff. He has a track record. And he’s likely to have a strong rebound any day now. For the Mariners, the question is whether he can be recast as a seventh-inning or matchup leverage weapon in a bullpen that already has a defined closer.

Antonio Senzatela - Colorado Rockies

This is a sneaky good fit. Probably the most intriguing name in this group because the role is not as clean and defined like the others. He’s going to want to be a starter again somewhere. But right now, he has been effective in relief, and that should create some curiosity for the Mariners.

Seattle could use a real bridge arm. Senzatela has been exactly that kind of weapon, going 6-0 with a 2.11 ERA, three saves and 32 strikeouts over 38 1/3 innings. If you want to focus on saving your bullpen arms without moving back to a piggyback plan, Senzatela can do that for you. 

He is also headed for free agency. We know the Mariners are not usually eager to overpay for rentals, so this only works if the price stays in the right neighborhood.

Kyle Finnegan - Detroit Tigers

This is a strong Matt Brash backup plan. And also, he comes from the only American League team on the list. It’s hard to see Detroit playing ball and trading with another AL team with their continued stance on contending this season. So if Finnegan becomes available, it’ll be close to the deadline, and the deal might be stiff. 

He’s an addition that would make a lot of sense if the Mariners want a clean late-inning answer without shopping at the top of the market.

He also won’t command a Jhoan Duran-type package. But Finnegan has been excellent for Detroit, posting a 2.01 ERA with 20 strikeouts over 31 1/3 innings and one save in 30 appearances.

Finnegan would help Seattle avoid leaning too hard on the same two or three relievers and allow the kind of late-inning flexibility that could win close games.

Jason Adam - San Diego Padres

This would likely be the most ideal and reasonable swing. Adams is fascinating because he checks multiple boxes.

He would be an impact addition. And he still would not be the kind of absurd, prospect-draining reliever trade.

Adam has been outstanding since arriving in San Diego. He has a 1.50 ERA with 17 strikeouts over 24 innings in 27 appearances this season, and the track record backs it up. Since joining them in 2024, he’s carried a sub-2.00 ERA

For the Mariners, this would be the cleanest baseball fit on the board. Adam would let Seattle use Brash more carefully. And he would make it easier to avoid asking Muñoz to rescue every narrow lead. 

The complication, of course, is San Diego. Despite the Padres spiraling down the power rankings, they won’t be a seller waiting for teams to come pick their bullpen apart. They’re still trying to contend, they have a lot of star power and they’re filled with way too many ridiculous contracts.  A.J. Preller doesn’t usually operate like a man interested in waving a white flag. So if Adam were to become part of a Mariners-Padres conversation, it probably wouldn’t be a simple prospect-for-reliever deal.

And that makes this possible acquisition even more interesting. Preller and Jerry Dipoto are two of the more creative executives in the sport. If there is a fit here, it could involve major-league pieces moving both ways. It could get weird in a hurry. And that might be the kind of chaos both teams need.

Adam would be the best version of what Seattle should be looking for, giving the Mariners a real leverage arm who improves the bullpen without putting even more pressure on Muñoz.