Major League Baseball’s annual Winter Meetings will take place in Orlando, Florida next week. We bring it up because this is another way of saying that all heck is about to break loose on the free-agent and trade markets, and the Seattle Mariners figure to be among the buyers.

However, that doesn’t mean they can’t also be sellers on the trade market. They have goods to offer and good excuses to move them, so let’s look at three members of the major league roster — i.e., not prospects, who got their own list — who could be on the trading block next week.

3 Mariners who could be on the trading block during MLB’s Winter MeetingsRHP Luis Castillo

Let’s get the obvious one out of the way first. Castillo’s name was one of the hottest on the trade rumor mill last winter, and he once again stands out as a trade candidate this winter.

With his no-trade rights having expired, the Mariners face one less hurdle in moving “La Piedra” if they so desire. But others still remain, with the gist being that his $24.15 million salaries for the next two seasons are a bit heavy for a 32-year-old (33 on December 12) who only has a 104 ERA+ to show for the last two seasons.

It only makes sense for the Mariners to move Castillo if they unload most or all of his remaining dollars and get at least one helpful player back in return, be it an MLB-ready prospect or an established major leaguer who would upgrade another part of the roster. If they can’t do that, their best move will be to hold onto Castillo and be grateful for what he still can do: eat innings in bunches.

LF Randy Arozarena

Along with Castillo, Arozarena was the other notable Mariner who looked like a trade candidate as soon as the offseason began. And he still does, in part because he’s projected to make a hefty $18.2 million salary via arbitration in 2026.

Perhaps that’s not too much for a two-time All-Star and former Rookie of the Year, but the Mariners have reason to suspect that this might be their last best chance to sell high on Arozarena. He’ll turn 31 on February 28, and he’s coming off a season in which his offense cratered at the end of the year. He had a .645 OPS in his last 53 regular season games, followed by a .574 OPS in the playoffs.

In Arozarena’s defense, his season was going just fine until Dan Wilson moved him to the leadoff spot. He was never well-suited for the role, so it’s entirely possible that his numbers will bounce back if he sticks in a lineup spot more conducive to his grip-it-and-rip-it style.

RF/DH Dominic Canzone

Between Canzone, Victor Robles and Luke Raley, the Mariners have a logjam in right field. And it will only become more congested if the team follows through on its pursuit of Jorge Polanco, who would block a path to playing time at designated hitter.

The Mariners are high on all three of these guys, but neither Robles nor Raley has much trade value after injury-marred 2025 seasons. There also isn’t a ton of money to be saved by dealing away either one of them. Raley is projected to make $1.8 million next year, while Robles is under contract for $5.125 million.

Canzone, on the other hand, is pre-arbitration-eligible and coming off his best season as a major leaguer, highlighted by a 142 OPS+ in 82 games. But since he’s strictly a platoon hitter who doesn’t offer much on the basepaths or on defense, the Mariners could reason that his value will never be higher and that it’s a good time to cash in.