Mariners Reportedly Open to Surprising Trade Deadline Move

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Mariners Reportedly Open to Surprising Trade Deadline Move

Originally posted on Athlon Sports | By Thomas Kelson | Last updated Jul 23, 2026 4:36 PM ET

The Major League Baseball trade deadline is less than two weeks away, and the Seattle Mariners are one of the most fascinating teams to watch.

The Mariners enter the day at 51-52, one game under .500 and just a half-game out of first place in the American League West. However, they haven't come close to matching last year's success, when they finished just one win shy of reaching the World Series.

Last year, the Mariners were ultra-aggressive at the trade deadline, trading five prospects for Josh Naylor and Eugenio Suárez. This year, their lackluster season has led to mixed reporting about how aggressive they'll be at the deadline.

It could even lead the Mariners to take a different approach by trading one of their top starting pitchers to capitalize on the market. The most frequently mentioned name has been right-hander Luis Castillo, who seemed like the obvious choice if Seattle went that route.

However, a new report suggests there's another pitcher Seattle is willing to move. Ken Rosenthal and Will Sammon of The Athletic reported Thursday that the Mariners have told teams they are open to trading right-handed starter Emerson Hancock.

Hancock is enjoying a breakout season in his fourth year with the Mariners. The former first-round pick is 6-4 with a 3.16 ERA over 105.1 innings, along with 97 strikeouts and a 1.01 WHIP. He also owns a pitching run value of 21, which ranks in the 98th percentile in baseball, according to Baseball Savant.

The Mariners are telling teams they are open to moving Emerson Hancock in their search for right-handed hitting, per @WillSammon.

Hancock has a 3.16 ERA in 105.1 IP and is under team control through 2030. pic.twitter.com/a7E75LlYmp
— Just Baseball (@JustBB_Media) July 23, 2026

The idea of moving Hancock is certainly surprising at first glance. Not only is he enjoying a breakout season, but he's also just 27 years old and remains under team control for four more seasons.

Still, Rosenthal and Sammon noted there may be some regression ahead. Hancock owns a 3.16 ERA, but his expected ERA sits at 4.31, suggesting some good fortune could be behind his breakout campaign.

On the other hand, Castillo has long been viewed as the more likely trade candidate. The 33-year-old is owed the remainder of his $22.7 million salary this season and another $22.7 million next year. Despite posting a 4.85 ERA, he's a far more established pitcher entering his 10th major league season.

If Seattle believes Hancock's value may never be higher, it could explain why teams have been told he's available.

As always, starting pitching will be one of the most sought-after commodities at the trade deadline. With many available starters either unproven or struggling, the Mariners could maximize their return by moving one of their six rotation arms.

Seattle can also afford to make that move because it has two of baseball's top pitching prospects waiting in the wings. Left-hander Kade Anderson and Ryan Sloan are both closing in on their major league debuts.

Teams desperate for pitching often overpay at the deadline, making this an ideal time for the Mariners to trade a starter.

This article first appeared on Athlon Sports and was syndicated with permission.

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