Three things to keep in mind as the Mariners embark on what might be the most important offseason in franchise history:
1. They have the fewest roster needs of the Jerry Dipoto/Justin Hollander regime.
2. They have the most payroll space they’ve had in the decade under Dipoto/Hollander.
3. They have one of baseball’s richest farm systems, with several highly regarded prospects expected to contribute at some point in 2026.
The Mariners got to the brink of the World Series this year because of an array of (mostly) sensible moves since the start of the franchise’s first full-blown rebuild in 2019.
There have been whiffs along the way, certainly, but in Cal Raleigh, J.P. Crawford and Julio Rodríguez the Mariners have constructed baseball’s best up-the-middle core, buoyed by a pitching apparatus that produces young arms nearly as much as your neighbor’s maple tree produces leaves all over your yard.
The window to contend is as open as it has ever been for the Mariners, and they’ve reached a point in their competitive cycle where they can afford to make a “luxury” splash (or two).
Now is not the time for discipline. With a chance to capitalize on all the momentum they created this October, the Mariners need to be bold this winter.
All that in mind, here are five moves the Mariners ought to consider this offseason:
1. Trade for the best pitcher on the planet
Late in the 2024 season, as Tarik Skubal was closing in on his first AL Cy Young Award, one MLB talent evaluator with four decades of pro baseball experience made an impromptu remark about the Detroit Tigers’ ace.
“He’s the best left-handed starter I’ve ever seen,” the veteran evaluator said.
Skubal was even better in 2025, and there are early reports this offseason that he could end up pitching elsewhere in 2026.
Skubal, who turns 29 on Nov. 20, will be a free agent after the 2026 season, and he’s expected to command the largest contract ever for a pitcher, a deal that could exceed $400 million.
That price range could be too steep for Detroit to re-sign him, and some have suggested Skubal, represented by mega-agent Scott Boras, could be on the trading block this winter if the Tigers come to that conclusion – that they’d want to get some package of prospects in return before he signs a free-agent deal with, presumably, one of the sport’s behemoths (the New York Mets or the Los Angeles Dodgers) a year from now.
And if the Tigers do listen to offers, the Mariners should be first in line with a pitch to acquire the left-hander who was inducted into the Seattle U Hall of Fame in 2024.
Here’s one proposal:
Mariners get: LHP Tarik Skubal
Tigers get: RHP Logan Evans, RHP/LHP Jurrangelo Cijntje, SS Felnin Celesten.
The Mariners, to be sure, would balk at this acquisition cost. All three players going to Detroit, in this exercise, are or have been ranked among the Top 100 prospects in the sport. For comparison, the Milwaukee Brewers got back only one Top 100 prospect (infielder Joey Ortiz, plus a reliever and a competitive-balance round draft pick) for ace Corbin Burnes going into 2024, a year before he hit free agency.
Evans pitched well for the Mariners this year as a 24-year-old in his first MLB season. Celesten is a 20-year-old switch-hitting shortstop with as much upside as just about anyone in the M’s system; and Cijntje, the switch-pitcher drafted in the first round in 2024, would be a painful prospect for the M’s to part with.
And perhaps it is excessive for what would surely be only one year of any pitcher’s services.
But this is Tarik Skubal … in his prime … and in his final season at a price point the Mariners could afford (he’s projected to earn about $18 million in his final year of arbitration).
The Mariners were thisclose to their first World Series, and Skubal is the type of talent – the bow around a well-rounded roster – that could push them to the mountain top.
It’s absolutely worth a shot.
2. Re-sign Josh Naylor
3. Re-sign Jorge Polanco
The Mariners have one of the best outfield situations in MLB, anchored by Rodriguez in center. Randy Arozarena will be back in left field in 2026 in his final season of club control before he reaches free agency next winter.
And, sure, free agent Kyle Tucker would be an ideal fit in right field in Seattle, but the idea of the Mariners giving any free agent a $400-million deal is about as far-fetched as your neighbor voluntarily cleaning up their leaves from your yard.
The Mariners already have a manageable – and affordable – situation in right field with Victor Robles and Dominic Canzone, and all indications are they’ll run it back with that outfield mix in ’26.
The infield is not quite as settled. The Mariners haven’t closed the door on re-signing Eugenio Suárez, but the more likely path is opening the door for two young players, Ben Williamson and top prospect Colt Emerson, to win the third-base job in spring training.
Cole Young, similarly, is the early front-runner at second base.
Which brings us to Naylor and Polanco, two of the team’s October heroes.
Naylor, 28, should be the Mariners’ top priority this winter and, by all accounts, he is. For one, they don’t have a second option at first. For another, Naylor proved to be the perfect fit in Seattle.
It’ll take the largest free-agent deal Dipoto and Hollander have given to a position player – likely four years in length, and somewhere in the $18-$20-million range per year.
Naylor’s worth it, and the Mariners will ultimately realize that.
It’s a similar discussion surrounding Polanco, who is coming off one of the best seasons of his career.
He is expected to decline a $6-million club option and enter free agency ahead of his age-32 season. He could seek a two-year deal in the $12-$14 million range and, like Naylor, he’s worth that to Seattle as a player who would split time between second base and designated hitter (and serve as the backup first baseman).
4. Trade Luis Castillo
Rumors swirled about Castillo on the trade block last offseason, and that could be the case again this winter.
This wouldn’t be an easy move to orchestrate on multiple fronts.
Castillo, first off, is an enormously popular figure in the Mariners clubhouse. He’s also been enormously productive and durable, posting a 3.46 ERA across 106 starts over the past three and a half seasons in Seattle.
He’s also the Mariners’ highest-paid player, scheduled to earn $24 million in each of the next two seasons, with a $25 million vesting option for 2028. The Mariners have given no indication they would want to trade Castillo or that they need to offload his contract, and it would be challenging to get equal value in return for him.
That said, a handful of clubs with bigger payrolls – New York Mets, San Francisco Giants, Philadelphia Phillies, San Diego Padres, Chicago Cubs, to name a few – figure to need starting pitching this winter, and Castillo would be a fit for all of them.
5. Sign a proven high-leverage reliever
Over the last handful of years, the Mariners have extracted more value from their bullpen than anywhere else on their roster (and perhaps as much as any team in MLB in that area).
This year alone, Seattle’s top four relief pitchers – Andrés Muñoz, Matt Brash, Gabe Speier and Eduard Bazardo – made a combined $5 million while finishing with a combined 6.6 Wins Above Replacement (via Baseball Reference).
Consider that, on the open market, a single WAR over the past couple years has been worth roughly $8-$10 million – and, yeah, that’s exceptional surplus value.
It’s time the Mariners use some of that savings and turn it into another proven late-inning reliever.
They should start by picking up all three options remaining on the club-friendly contract Muñoz signed in 2022. That deal guaranteed Muñoz $7.5 million over four seasons (through 2025), with a $6 million option for ’26, $8 million for ’27 and $10 million for ’28.
Muñoz has blossomed into one of the game’s elite closers, and guaranteeing the $24 million over the next three seasons is still a bargain for the Mariners – and, more importantly, it’ll bring Muñoz some peace of mind after he closed out this season under a cloud of contract uncertainty.
Next step: Bring in Devin Williams on a one-year, $10-million free-agent deal.
Williams, 31, had been an elite closer with the Brewers before being traded to the Yankees before the 2025 season. He posted a career-high 4.79 ERA in New York, but his underlying data remained strong this year – his changeup is still one of baseball’s most valuable pitches – and he would be a smart addition on a short-term deal.
Adding a reliever of Williams’ caliber is exactly the sort of “luxury” item the Mariners should be shopping for this winter. They’ve built up credible capital among an eager fan base, and they should invest it following their momentous October.