Each offseason over the past few years has seemed like the biggest one in recent memory for the Seattle Mariners.

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Whether it was trying to build off a playoff run following 2022 or trying get over the hump after falling one game shy of reaching the postseason following the 2023 and 2024 campaigns, the winter months felt like the prime opportunity for the M’s to finally make themselves a true World Series contender. Now, after coming only one win shy of the Fall Classic, this offseason is clearly the most important for the M’s under president of baseball operations Jerry Dipoto and general manger Justin Hollander.

To the M’s credit, they’ve addressed some of their biggest needs so far. Josh Naylor is back after signing a five-year deal. They added a left-hander reliever with nasty stuff and a high ceiling in Jose Ferrer. And they picked up a a veteran bat who mashes left-handed pitching in Rob Refsnyder.

But Seattle’s offseason isn’t complete just yet. There is still a big need for another impact infield bat.

The Mariners have notably been linked to a pair of trade targets on the infield: Cardinals utilityman Brendan Donovan and Arizona Diamondbacks second baseman Ketel Marte. They’re reported to be one of two finalists for Donovan.

However, the M’s may fall short in their pursuit of those bats. If they do, what other options are out there? Here’s a look at some of potential impact infield bats outside of Donovan and Marte who are still on the free agent market or are considered to be available via trade.

Eugenio Suárez

Another reunion with Suárez is the most obvious pivot for the M’s if they don’t land Marte or Donovan, as long as it’s a short-term deal for the 34-year-old third baseman. The Mariners know what they would be getting in the veteran. He’s a beloved figure in the clubhouse that can carry an offense when his bat his hot, but has the tendency to go ice-cold for stretches. He could be the starter at third base to begin the season, and if top prospect Colt Emerson or Ben Williamson show enough to earn playing time there, he can slot over into more of a DH role.

Kazuma Okamoto

Okamoto isn’t a perfect since he’s expected to play first base, but the Japanese slugger is still a viable option for the M’s. He hit at least 27 homers for the NPB’s Yomiuri Giants in each season from 2018-24, and despite being limited to just 69 games in 2025 due to an elbow injury, he still slugged 15 homers and hit .327 with a 1.014 OPS. The 29-year-old Okamoto primarily played third base in the NPB, so that would seemingly still be an option if he came to Seattle. He could also fill a primary DH role and be a right-handed option at first base if the M’s want to Josh Naylor a day off against a tough left-hander. Okamoto’s deadline to sign with an MLB team is Jan. 4.

Willi Castro

The switch-hitting Castro’s versatility makes him an intriguing fit for the M’s. The 2024 All-Star could play either second or third base, and he’s played every position except catcher and first base throughout his seven-year career. He’s also been a solid hitter for most of the past three seasons. In 358 games for the Twins from 2023-25, he hit .250 with a .733 OPS, 107 extra-base hits and a 107 wRC+. But he’s coming off a dreadful 34-game stint after being to the Cubs last season in which he batted .170 with a .485 OPS and 40 wRC+. Castro’s rough final two months might be why he’s still available. If it leads to a one-year, prove-it deal, he would make a lot of sense for the M’s.

Alec Bohm

Bohm has been a name that has come up often as a trade target for the Mariners. He has just one-year of club control remaining, so he could be a stop-gap answer at third base with Emerson or Williamson waiting to take over and move to more of a DH role at some point in 2026 if needed. He can also play first and provide some insurance behind Naylor. Like Suárez and Okamoto, Bohm doesn’t check all of the right boxes for the M’s since he doesn’t play second base. But he has been a steady hitter with a wRC+ of 104 or better in each of the past three seasons. And while his defense is still below average, it’s gotten much better over the past two years.

Mark Vientos

Vientos is another trade option that plays third base and could fill in at first. The right-handed-hitting third baseman had a strong 2024 campaign, slugging 27 homers while hitting .266 with an .837 OPS and 132 wRC+ in 111 games. But his numbers dipped considerably in 2025 with 17 homers, a .233 average, .702 OPS and 97 wRC+ in 121 games. There’s also strikeout concerns (a career 28% strikeout rate) and he’s a poor defender at third. Vientos is still just 26, has four years of club control remaining and there’s some intriguing power potential, but he feels like a real risk, especially for a team that plays 81 games at T-Mobile Park. Plus, the years of club control mean he wouldn’t come cheap in a trade.

Seattle Mariners offseason coverage

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