Seattle Mariners third baseman Miles Mastrobuoni reacts after hitting a single against the New York Yankees on July 10 at Yankee Stadium. Brad Penner-Imagn Images

Seattle Mariners Option Utility Player to Make Room For New Trade Acquisition

Originally posted on Seattle Mariners on SI
By Teren Kowatsch | Last updated Jul 25, 2025 6:30 PM ET

The Seattle Mariners newest trade acquisition has officially reported to the club.

Mariners PR announced on "X" that first baseman Josh Naylor, who the team acquired in a deal with the Arizona Diamondbacks on Thursday, reported to the club ahead of a game against the Los Angeles Angels on Friday.

In a corresponding move, Seattle optioned utility player Miles Mastrobuoni to the Triple-A Tacoma Rainiers.

Roster moves:

Josh Naylor, INF, reports to club.
Miles Mastrobuoni, INF/OF, optioned to Triple-A Tacoma.

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— Mariners PR (@MarinersPR) July 25, 2025

Mastrobuoni was acquired by the Mariners in a trade with the Chicago Cubs on Jan. 14, 2025, in return for cash considerations.

Mastrobuoni has been used in a utility role this season and has recently received playing time as a late-game pinch-hitter.

Mastrobuoni has scored 19 runs in 71 games this season. He's hit three doubles and a home run with 12 RBIs and has stolen five bases. He's slashed .252/.327/.293 with a .620 OPS. He's played at least nine games at second base, third base, left field and right field this season.

Miles Mastrobuoni keeps the game alive with an incredible over-the-shoulder catch!

(via @MLB)pic.twitter.com/qwGJJM6BLk
— FOX Sports: MLB (@MLBONFOX) June 28, 2025

Mastrobuoni has done well in his role with the team, but the Mariners have dept in the outfield and at first base with the addition of Naylor.

Luke Raley can play first base and the outfield, Donovan Solano can play first base and Dominic Canzone has played a solid right field for Seattle since being recalled from Triple-A. Dylan Moore, despite struggling at the plate this season (.201/.264/.374 slash line), is a Gold Glove-winning utility player that can also play the infield and outfield.

Naylor will make his debut for Seattle in a game against Los Angeles at 6:38 p.m. PT on Friday. Naylor will bat cleanup for the M's.

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

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