Mariners DFA Miles Mastrobuoni as Weston Wilson Gets Immediate Shot vs. Red Sox

This is not a blockbuster move, but it could still be a big play.

Jun 14, 2026; Washington, District of Columbia, USA; Seattle Mariners third baseman Miles Mastrobuoni (21) walks back to the dugout after striking out against the Washington Nationals during the second inning at Nationals Park. Mandatory Credit: Rafael Suanes-Imagn Images | Rafael Suanes-Imagn Images

Welp, that escalated quickly. A few days ago, Weston Wilson looked like a perfectly reasonable minor-league signing. Nothing really seemed too dramatic about it. And now he’s already on the big-league roster. That alone tells us this signing was more intentional than we imagined. 

The Mariners designated Miles Mastrobuoni (.217/.269/.217) for assignment and selected Wilson before this weekend’s series against the Boston Red Sox. Honestly, it kind of writes itself. The Red Sox are rolling out lefty starters in all three games, and the Mariners had a near all-lefty infield. Wilson at least changes that. 

Mastrobuoni’s stint always felt temporary, but the timing is still a little jarring. He had a knack of surviving roster crunches over the season due to his flexibility around the diamond. His bat never really matched that same staying power. 

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Mariners Turn Weston Wilson Into an Immediate Factor After Surprise DFA

Wilson gives them a different type of emergency option at a time when the roster needs more than just positional flexibility. They need someone who could run into a baseball, especially if their other right-handed options struggle. It’s a worthy gamble. 

The former Phillies and Orioles utility player has enough pop, experience, and defensive versatility to make sense for a Mariners team that keeps having to adjust on the fly. He can cover the corner infield and corner outfield spots as well. 

In a perfect world, this would not be the weekend where a recent minor-league signee suddenly becomes relevant. But like it or not, that’s where the Mariners are living right now.

Randy Arozarena is still hurt. Josh Naylor has been banged up. Julio Rodríguez too. Though they both are back in the lineup. The outfield depth has been stretched thin enough that Curtis Washington Jr. got a one-day big-league cameo before Connor Joe arrived. None of this is normal roster behavior. And you can add this most recent move to the list. The Mastrobuoni DFA might be surprising. But it’s certainly not confusing.

The Mariners are wasting no time with this move. Wilson is tonight’s starting third baseman with Bryce Miller on the bump. J.P Crawford will take a seat, and Colt Emerson will continue working shortstop. All of that is worth paying attention to. 

Rob Refsnyder is also batting leadoff against his former team. Refsnyder has been struggling all season, which makes this quite the audition for Wilson. What if Wilson outperforms Refsnyder this weekend? We’ll have a lot more to talk about if that’s the case.