Jon Heyman of the New York Post connected the Seattle Mariners to Ketel Marte on the trade market on Sunday night, and on Monday morning, Jon Morosi of MLB Network confirmed that the Mariners are indeed in the conversations for both Marte and Brendan Donovan of the St. Louis Cardinals.

At the end of the day, both players would help the Mariners achieve their goal of repeating as American League West champions, and they both would help the M's be in a stronger position to get back to the American League Championship Series in 2026.

But, trading for both players could be painful, in multiple ways.

On a surface level, Marte's $90 million contract is relatively affordable, but still, taking on $18 million a year could limit the Mariners from doing other things this offseason - and beyond. Acquiring either player likely means that Cole Young is done as an everyday option in Seattle, which is a painful resolution for a Top-100 prospect.

But the real pain will come in the form of the additional prospect cost.

We know that if the Diamondbacks are trading Marte, an All-Star with six years of team control, they are going to want a boat load in return. We know that the Cardinals aren't just giving away Donovan and his two years of team control, for free, and we know they want pitching.

And that's where it's going to hurt the Mariners.

See, I made the point on one of the most recent Refuse to Lose podcasts that the M's development of young pitching is one of their biggest storylines of 2026, and that's because the Mariners likely can't keep Logan Gilbert and George Kirby in the future, and because Luis Castillo's contract is set to end after 2027.

As a result, the M's will need the group of young pitchers to develop through the system and be ready to take their places in possible short order, but these deals will certainly impact those plans.

If the Mariners acquire Donovan, they'd almost assuredly have to give up at least one of Ryan Sloan, Jurrangelo Cijntje and Kade Anderson. If they acquire Marte, it could be two of those arms. Given where the pitching staff is headed in the future, those could have devastating consequences. We spoke with Buster Olney of ESPN about the situation facing the M's pitching last week as well.

"As we go forward and the Mariners make their choices, keeping that pipeline talent developed is the most important thing," Olney said on the podcast. "If you are not going to be a team that spends money like the Mets or the Yankees or the Dodgers or the Blue Jays, you have to keep that pipeline of talent going. When we talk during the winter time and we talk about potential asking price for a guy like Tarik Skubal, if you're the Mariners, the first thing you're doing is protecting that young group of players that you have and not using those assets if you're not prepared to spend that kind of money."

More Mariners stories

After acquiring Jose Ferrer, how does the Mariners bullpen look?

Reasons for optimism if the Mariners bring back Mitch Garver

Could the Mariners be a fit for Luke Weaver this offseason?

Join the Conversation

Remember to join our MARINERS on ROUNDTABLE community, which is FREE! You can post your own thoughts, in text or video form, and you can engage with our Roundtable staff, as well as other Mariners fans. If prompted to download the Roundtable APP, that's free too!