Seattle Mariners third baseman Ben Williamson celebrates in the dugout after scoring a run against the Kansas City Royals on July 2 at T-Mobile Park. John Froschauer-Imagn Images

Seattle Mariners Option Rookie Infielder to Make Room For Eugenio Suarez

Originally posted on Seattle Mariners on SI
By Teren Kowatsch | Last updated Jul 31, 2025 6:38 PM ET

The Seattle Mariners pulled off arguably the biggest deal of trade deadline season by acquiring All-Star third baseman Eugenio Suarez from the Arizona Diamondbacks on Wednesday.

The package to acquire Suarez included first baseman Tyler Locklear, who was recalled from the Triple-A Tacoma Rainiers the same day the deal took place. Two pitching prospects were also traded in Hunter Cranton and Juan Bergos.

There were more dominoes that fell as a result of the Suarez swap.

Seattle announced Suarez officially reported to the club Thursday. In corresponding moves, rookie third baseman Ben Williamson was optioned to Triple-A and utility player Miles Mastrobuoni was recalled from Tacoma.

Roster moves:

Eugenio Suárez (#28), INF, reports to club.
Miles Mastrobuoni, INF/OF, recalled from Triple-A Tacoma.
Ben Williamson, INF, optioned to Triple-A Tacoma.

The @Mariners 26-man active roster is now full at 26 players.
— Mariners PR (@MarinersPR) July 31, 2025

Williamson was picked by the Mariners in the second round of the 2023 MLB Draft. He had his contract selected by the team April 13. He's been the team's starting third baseman since and has arguably been the M's best defensive infielder.

Williamson has scored 36 runs in 85 games this season and has hit 13 doubles and a home run with 21 RBIs. He's slashed .253/.294/.310 with a .604 OPS.

the stop ‼️
the throw ‼️ pic.twitter.com/M2mlKlSSTg
— Seattle Mariners (@Mariners) July 29, 2025

Mastrobuoni was optioned to the Rainiers on July 25. He spent the entirety of the season on the 26-man roster until that point.

Mastrobuoni has been a valuable utility player off the bench for Seattle and has occasionally stepped into the starting lineup due to injuries. He's registered time at second base, third base, left field and right field this year.

Mastrobuoni has scored 19 runs in 71 games and has hit three doubles and a home run with 12 RBIs. He's slashed .252/.327/.293 with a .620 OPS.

MILES MASTROBUONI WITH AN INCREDIBLE CATCH‼️ pic.twitter.com/7xaWLDGr9B
— Seattle Mariners (@Mariners) June 28, 2025

Suarez, Mastrobuoni and the rest of the Mariners will begin a four-game series against the Texas Rangers at 6:40 p.m. PT on Thursday at T-Mobile Park.

This article first appeared on Seattle Mariners on SI and was syndicated with permission.

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