#2 Mariners need: Lights Out Relievers
Seattle's bullpen has been decent this year. Aside from Cleveland's reliever wizardry, the Mariners aren't too far behind the best. Their 3.71 ERA is 11th in MLB but that result is a little more lopsided than one might think. Andrés Muñoz has been incredible, posting a 1.42 ERA, 0.95 WHIP, and 11.9 SO/9 over 31.2 innings pitched. Austin Voth has appeared in late-inning non-save situations and has pitched to a 2.93 ERA and 0.88 WHIP over his 30.2 innings.
Outside of those two names, no one else in the bullpen has a WHIP below 1.00 and only Ryne Stanek has more than 10.0 SO/9. This isn't the end of the world, (you could always be the Angels bullpen) but in the high-pressure context of the postseason, more reliever arms can be the difference between a win or a loss, especially if the rotation slips up.
Seattle has done well to work with what they have but another strong, strikeout-oriented bullpen arm could be a huge addition for the team. With his 99 mph sinker and 91 mph slider, Gregory Santos could be that missing piece for the Mariners, but he's just now getting around to pitching at full force and has yet to start his rehab assignment. Even when he finally makes it off the IL, how much time will he need to pick up where he left off in 2023? Either way, it might not hurt to bolster the bullpen with another live arm.
Possible Names: RHP Colin Holderman (PIT), RHP Kirby Yates (TEX), RHP Ryan Walker (SFG)