The Seattle Mariners current projeted infield for 2025 more resembles a piece of swiss cheese than it does a legitimate MLB defense.
The Mariners have holes at first base, second base and third base that all need to be filled by the time the team takes the field on Opening Day against the Athletics on March 27.
Seattle owner/chairman John Stanton has already said that the club won’t be big spenders in free agency, eliminating potential solutions like Alex Bregman or Juan Soto from the equation.
But even if Stanton didn’t make that proclamation, the Mariners have famously looked to the trade market to find answers in positions of need. That’s been the case in all nine years current President of Baseball Operations Jerry Dipoto has been in the front office.
And Seattle was mentioned as a potential trade destination for an eight-time All-Star in an article published by MLB.com’s St. Louis Cardinals beat writer John Denton on Monday.
In the article, Denton went over several Cardinals players that could be moved in the offseason. And among the list of players was six-time Platinum Glove Award winner and five-time Silver Slugger Nolan Arenado.
Denton mentioned in the article that Arenado has expressed wanting to play for a contender in an effort to win a World Series ring, the one honor missing from his likely-Hall of Fame resume.
Denton said the following about Arenado in the article:
“Arenado, 33, has mentioned repeatedly that he feels the clock on his career ticking, and he wants to be on a team that can compete for a World Series. Could he be a cheaper option for the Astros if they lose free-agent third baseman Alex Bregman, or would he consider the Dodgers, Angels, D-backs or Mariners?”
Arenado, who played for the Colorado Rockies from 2013-2020 and St. Louis from 2021-present, has never even made a League Championship Series in his 12-year career.
Arenado has a no-trade clause in his contract, meaning he has to give the seal of approval to any move involving him.
But depending on the team, that shouldn’t be a problem. According to several rumors, the Cardinals already informed Arenado that they’re planning on moving him in the offseason. Arenado, according to the same rumors, has agreed to the process and is working hand-in-hand with St. Louis to find a home.
Arenado is coming off a down year by his standards. He batted .272 with 16 home runs and 71 RBIs in 152 games played in 2024. It’s the first time he’s failed to clear the 20-home run mark since his second season in the league in 2014. Not including the COVID-19-shortened 2020 season.
There’s several pros and cons for Seattle to make this deal.
The pros: Arenado, even in his mid-30s, is one of the best defensive third basemen in the league. Maybe one of the best defensive infielders period. He had nine outs above average, which puts him in the 94th percentile in the MLB, according to Baseball Savant. And even though 2024 was not a typical season for him offensively, those numbers would still represent a significant boost than what the Mariners got from Josh Rojas at third base in 2024.
Arenado’s defense would also avoid a potential quality drop in fielding at third. Despite his offensive struggles, Rojas still was a Gold Glove-caliber third baseman in 2024.
Now for the cons: Arenado is set to earn $21 million in 2025, $16 million in 2026 and $15 million in 2027 in the remaining three years on his contract. That’s three years totaling $52 million for a player who’s numbers have steadily declined.
In St. Louis, Arenado’s batting average from 2021-24 has been .255, .293, .266, .272. Normally that would be fine if the home runs stayed high. But his numbers have also steadily dipped in that category. From 2021-24, Arenado’s home runs were 34, 30, 26, 16.
The last con is that, even coming off of a down 2024, it would still cost a lot to acquire Arenado. The Mariners have been stingy about letting go of their top prospects. It would likely take two top 15 prospects and Josh Rojas to bring Arenado to Seattle. If the Mariners refuse to include prospects, the Cardinals would likely ask for a starting pitcher from Seattle’s elite rotation.
Most fans will also point out the fact that T-Mobile Park and the Marine Layer is a difficult hitting environment. But the St. Louis’ home field of Busch Stadium isn’t exactly a welcoming setting to batters, either. Hitters knocked out 96 home runs at T-Mobile Park compared to 91 at the Cardinals’ home field of Busch Stadium.
T-Mobile Park is dead last among MLB ballparks in Park Factor (91) and Busch Stadium ranks 18th (100) according to Baseball Savant.
If the Mariners were to trade for Arenado, it would likely be for the remainder of his three-year deal. He’ll be 36 when his contract ends and he likely won’t waive his no-trade clause for the second time in a four-year period. He would also be the highest-paid player on the roster for 2025. Julio Rodriguez, the franchise star, is set to earn $19.9125 million next year.
If Seattle is serious about adding a legitimate bat to its lineup, it’s going to have to fork up some money somewhere. Even if it’s not in free agency, there’s not a lot of capable hitters who play the Mariners’ positions of need who aren’t making at least five figures. The players who are on a cheap salary like the Baltimore Orioles’ Jordan Westburg would still require a decent haul to bring to the Pacific Northwest.
The Mariners have gone for veterans in the past to try and boost the offense to little to no avail. Jorge Polanco and Mitch Garver have been two recent examples of that. But neither Polanco, Garver or any others Seattle has brought in has the power-hitting profile of Arenado combined with the elite defense.
There’s a chance Arenado bounced back in 2025 and Seattle ends up getting a steal, even while on the hook for $21 million.
But there’s also a chance that Arenado continues his decline and the Mariners end up paying $21 million to a future Hall of Famer with his best years behind him.
It’s a gamble. One that might be too high-risk for Seattle to buy in on.
