MLB Rumors: Mariners & Cardinals Talking Trade

December 30, 2025 ,

Seattle Mariners manager Dan Wilson reacts during 2025 game.

The Seattle Mariners are making it clear they want a real lineup upgrade, and they think St. Louis Cardinals super-utility man Brendan Donovan fits the bill. 

Multiple reports say Seattle and St. Louis have already had lengthy discussions, with the Mariners willing to build a prospect-heavy package that could include switch pitcher Jurrangelo Cijntje.

Brendan Donovan trade talks are real and Seattle is pushing

Mariners' beat writer Ryan Divish’s reporting frames Seattle’s front office as motivated to keep adding, and Donovan checks a bunch of boxes because he can move around the infield and outfield while bringing steady on-base skills with two years of club control. 

The tension point is what St. Louis wants back, since the Cardinals’ decision makers know Donovan is a premium trade chip and multiple teams are in the mix.

Seattle’s interest also lines up with how the market has been framed for weeks, with the Mariners and San Francisco Giants previously mentioned among the teams circling Donovan.

This past season, Donovan slashed .287/.353/.422, with 10 home runs, 50 RBIs, three stolen bases, and 64 runs scored across 118 games played. He also made his first All-Star game.

Why the Mariners refuse to trade big league starters

However, even while they are willing to move high-end prospects, the Mariners are digging in on one major boundary: they do not want to trade established starters off the major league roster to get Donovan. 

That stance has reportedly been consistent from Jerry Dipoto and Justin Hollander, and it helps explain why this has stayed in the “active talks” phase instead of crossing the finish line.

Seattle views its rotation as the team’s biggest advantage, and the depth behind it is shaky enough that subtracting a proven starter could create a new problem while trying to solve the offense. 

The Mariners can sell St. Louis on upside arms like Cijntje, but the Cardinals have also been linked to seeking more immediate major league pitching, so the trade’s shape may come down to whether St. Louis is willing to bet on the next wave instead of demanding present-day rotation help.

Photo Credit: Eric Hartline-Imagn Images

Go To: NFL Rumors | NBA Rumors | NHL Rumors