Mariners Could Target Former All-Star As Potential Offensive Upgrade

The Mariners still have some work to do.

May 12, 2018; Detroit, MI, USA; Hat and glove of Seattle Mariners center fielder Dee Gordon (9) sits in dugout during the third inning against the Detroit Tigers at Comerica Park. Mandatory Credit: Rick Osentoski-Imagn Images | Rick Osentoski-Imagn Images

The Seattle Mariners have had a mixed bag of an offseason thus far. They managed to keep Josh Naylor around for the next five years, but also lost Jorge Polanco to the New York Mets.

They need a little bit of help offensively, particularly at second base. They have been in on both Brendan Donovan and Ketel Marte, but there is no guarantee they’ll actually be able to acquire either one of them.

They might have to dive into the free agent market for some help. Zachary D. Rymer of Bleacher Report lists infielder Willi Castro as a buy-low free agent and had Seattle as a possible fit for him.

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Mariners Still Need Some Offense For 2026

Sep 20, 2025; Cincinnati, Ohio, USA; Chicago Cubs outfielder Willi Castro (1) scores a run against the Cincinnati Reds in the eighth inning at Great American Ball Park. Mandatory Credit: Aaron Doster-Imagn Images | Aaron Doster-Imagn Images

Castro was having a solid year offensively before ultimately struggling late in the year. The Minnesota Twins sent him to the Chicago Cubs, and things went south.

He finished the season hitting .226/.313/.366 with 11 home runs, 33 RBI and a .679 OPS. However, he can still generate some offense when he’s at his best. He even stole 10 bases in 2025.

If he can replicate his numbers with Minnesota, he could still be a solid offensive piece. He can play all three outfield positions as well as second base and shortstop. 

He won’t cost much after having struggled with the Cubs, but he also wouldn’t require the Mariners to give up a big haul via trade, which is something they would have to do in order to land a player such as Donovan or Marte.

Castro is also a switch-hitter, so he can be a dual-threat from both sides of the plate and match up well against any pitcher.

The Mariners have a clear need for a little more offense, and Castro could be a much cheaper solution than having to make a blockbuster trade and give up several top prospects. He wouldn’t force the Mariners to break the bank or give up any Major League ready starting pitching.

It will be interesting to see what president of baseball operations Jerry Dipoto decides to do, but he has other options besides having to give up prospects for somebody like Donovan or Marte.

Castro could fit the bill of what the Mariners are looking for as they try to beef up their offense for 2026.

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