Facing a Monday at 2 p.m. PT deadline to get their 40-man roster in compliance for the start of the 2027 league year, the Seattle Mariners made multiple moves.

Here's what you need to know.

As first reported by Francys Romero, the Mariners issued the QO to Arozarena, who is coming off back-to-back All-Star campaigns.

The qualifying offer is a one-year contract worth about $23 million. If Arozarena accepts, he'll be back with the Mariners at that number in 2027. If he declines, as he's expected to, he'll hit the open market as a free agent.

If and when he signs with another team, the Mariners will receive draft pick compensation.

Per Joe Doyle of OverSlot Baseball:

Assuming Randy Arozarena rejects this and signs with another team for a contract exceeding $50m in total value, the Mariners will receive a Compensation Pick after the first round of the 2027 MLB Draft for losing Arozarena (assuming nothing changes in the new CBA).

Arozarena is expected to be one of the most coveted free agents on the board this offseason. He had 26 home runs and 26 stolen bases this season for the M's, serving as the best offensive piece, by far, on a subpar offensive team.

A 31-year-old right-hander, Mattson is a four-year veteran of the Baltimore Orioles and Pittsburgh Pirates. He struggled to a 5.35 ERA in 38 games this past season, but was much better in 2025, when he went 3-3 with a 2.45 ERA in 44 games. For his career, he has 90 strikeouts in 96.0 innings.

He's an interesting project for the Mariners in the bullpen, but he's not the kind of home run reliever they need right now. That said, he'll be a fun follow through the offseason and spring.

The Mariners brought back multiple players from 60-day injured list in order to get them back on the 40-man roster. This includes Matt Brash, Luke Raley, Nick Davila, Brennen Davis, Colt Emerson, Logan Evans and Michael Toglia.

In order to get into compliance with the 40-man roster, the Mariners had to make multiple moves as well.

They have outrighted Josh Simpson, Troy Watson, Weston Wilson, Will Wilson and Patrick Wisdom to Triple-A Tacoma.

Not every one of those players will remain in the organization. Some of them will be able to reject the assignment and choose free agency instead.

The Mariners 40-man roster is now at 39.

The Mariners are free to negotiate with all players. We have about one month until the probable MLB lockout takes hold.