Predicting 3 Mariners Who Already Played Their Last Games In Seattle

Which departures are on the horizon?

Oct 15, 2025; Seattle, Washington, USA; Seattle Mariners third baseman Eugenio Suárez (28) throws to first for an out during the first inning against the Toronto Blue Jays during game three of the ALCS round for the 2025 MLB playoffs at T-Mobile Park. Mandatory Credit: Steven Bisig-Imagn Images | Steven Bisig-Imagn Images

The Seattle Mariners are certain to have at least a slightly different look when they next take the field.

Coming off a gut-wrenching loss in Game 7 of the American League Championship Series, the Mariners know they have a winning formula moving forward. But not everyone on the postseason roster will have the privilege of remaining in the equation.

So, as we start to construct the ideal plan for the Mariners' offseason in our heads, here are three players Fastball on SI believes have played their final games in a Seattle uniform.

Eugenio Suárez - 3B

EUGENIO SUÁREZ CONNECTS AGAIN IN GRAND FASHION 🤯

WHAT A GAME IN SEATTLE 🔥 pic.twitter.com/9BQVmonoum

— MLB (@MLB) October 18, 2025

The Mariners aren't going to bring back all three of their top free agents, and Suárez seems the most likely to go. Coming off a 49-homer season, he'll probably land at least a lucrative two-year contract, and once again, he wasn't able to conquer T-Mobile Park and put up numbers in line with his career averages.

While Seattle fans will always love him for his grand slam in Game 5 of the ALCS, it's more likely than not that we've seen the last of Suárez as a Mariner.

Caleb Ferguson - RP

It wouldn't be a total shock to see the Mariners run it back with Ferguson, who they acquired from the Pittsburgh Pirates at the trade deadline. But he had two blowup outings in the postseason, and even though he's only 29, he's put a lot of mileage on his arm over the last few years.

Ferguson has already pitched for five teams at the major league level, and the guess here is that he'll be looking for team No. 6 in short order.

Luis Castillo - SP

Oct 16, 2025; Seattle, Washington, USA; Seattle Mariners pitcher Luis Castillo (58) throws in the second inning against the Toronto Blue Jays during game four of the ALCS round for the 2025 MLB playoffs at T-Mobile Park. Mandatory Credit: Kevin Ng-Imagn Images | Kevin Ng-Imagn Images

We had to go with a bit of a wild card for our last entry on the list. Castillo is under contract for at least two more years, and is currently slated to be the Mariners' highest-paid player next year at $24 million. But he's entering his mid-thirties and it's unclear how much longer he can keep making 30-plus starts per season.

If the Mariners can get a team to eat Castillo's entire contract this winter, they might seriously consider that possibility, which would allow them to reallocate some money toward building a better top-to-bottom lineup.

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