If you go on social media and look at offseason proposals from Seattle Mariners fans and content creators, a lot of them include the idea of trading away starting pitcher Luis Castillo.

Some plans cite Castillo's burgeoning age (almost 33), while others cite his contract (approximately $50 million over the next two guaranteed seasons) as reasons to get rid of him. 

However, as you read these proposals, you need to have the following PSA's in mind:

You will never clear all of Castillo's money

It's an understandable idea, right? If you trade Castillo, you clear the money to go and sign other players who can help the Mariners more.

However, it's not fully realistic. The Mariners would never be able to trade Castillo for no money back. For example, if the Mariners traded a $24 million Castillo and took a $10 million player in return, they'd only clear $14 million in that case.

And while that would help, it's not the full $24 million that people are hoping for. Furthermore, if the Mariners were to trade for an inexpensive player, the acquiring team would ask the Mariners to take on some of Castillo's salary, also not freeing up the money that people think is available.

Moving Castillo could certainly help financially, but would the savings be enough to meaningfully help the Mariners, while also putting a hole in the rotation?

Innings-eaters are valuable

As stated on the most recent edition of the 'Refuse to Lose' podcast:

On the Castillo front, we saw how valuable and volatile pitching is in 2025. For as good as the Mariners were in the 90-win season, Logan Gilbert was lost for a month, Bryce Miller was lost for half the season, Bryan Woo was lost for the final part of the regular season, and virtually all of the playoffs, and George Kirby was out for a month and a half.

While Castillo is not the ace that he was when they acquired him in 2022, he was 'The Rock' in the sense that he was consistent and he took the ball.

After what we saw this year, I don't think just banking on pitcher health is the right way to go about this. And by the way, I saw some of the projections on other pitchers who are free agents, like Shane Bieber, coming off Tommy John surgery making 7 starts in 2025, was projected by Baseball America at 5 years and $150 million. So if a guy like that is getting $30 million a year, then Luis Castillo at $24 million a year, I'm not going to necessarily call it a bargain, but I'm also not going to say that it is egregious either. So, Castillo is a guy at this point that I'd rather keep. Again, I can, I can change my mind depending on what else happens, but I see the value in keeping Castillo.

Castillo went 11-8 with a 3.54 ERA for the Mariners this season, helping them win the American League West for the first time since 2001.

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LATEST PODCAST IS OUT: Brady Farkas is back for the the latest episode of the Refuse to Lose podcast! He talks about the end of the World Series and the end of Mitch Garver's tenure in Seattle. Furthermore, he issues a PSA to those who want to trade Randy Arozarena, Luis Castillo and JP Crawford. He's also joined by FOX 13 Sports Director Aaron Levine, who talks about his three-day winning streak on Jeopardy! from last week. CLICK HERE: 

GOOD ODDS: The Mariners have been given good odds to win the World Series in 2026. Here's where they stand. CLICK HERE: 

WILL M's CHANGE STYLE? The Blue Jays are having success with a contact-driven approach in the playoffs. Will that change how the M's play offense moving forward? CLICK HERE: 

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