MLB insider pitches a nonsensical Mariners trade for washed up All-Star

MLB Network insider Jon Morosi is back on the “Nolan Arenado to Seattle” carousel again, floating the idea that the Mariners are a potential landing spot for the veteran third baseman. In a vacuum, “future Hall of Famer at a position of need” is an easy sell. Mariners fans have watched this lineup go ice-cold at the worst times for years. A big name can always sound like the cure.

But the version of Arenado you’re trading for in late 2025 isn’t the one that used to terrorize pitchers in Colorado. The latest body of work is the problem. Arenado just posted career lows across the board offensively, slashing .237/.289/.377 with a .666 OPS, and finished at 1.3 bWAR. And that’s where the whole pitch starts wobbling.

Nolan Arenado to Seattle sounds big until you look at the Mariners’ actual plan

Morosi’s argument, which he pitched on Thursday during an interview with Wyman and Bob on Seattle Sports, includes the idea that Arenado wants a “winning environment” and could be a “mentor” for 25-year-old third baseman Ben Williamson. Cool concept — except mentoring gets a lot harder when you’re occupying the exact spot the kid needs to play.

Obviously, Arenado wouldn’t be coming here to learn first base. You don’t want him at DH. You’d be trading for him because he plays third.

Meanwhile, the Mariners have been pretty loud about what they think they already have. Jerry Dipoto called Williamson “an elite defender,” and tied his glove directly to Seattle shifting toward more of a ground-ball identity: “having a third baseman that can really pick it is really important.”  That is not a quote from a front office preparing to hand the hot corner to a 35-year-old on a nine-figure reputation tour.

Here’s the part that makes the rumor feel especially dated: Williamson is already doing the “glove first, bat TBD” thing just fine — and he matched Arenado’s 2025 bWAR (1.3) while being roughly a decade younger and significantly cheaper. 

So yeah. If the Mariners want a veteran bat to help Williamson, the clean solution is… not trading for a veteran who takes Williamson’s job. Sometimes the smartest move is the one you don’t have to talk yourself into.