New MLB Trade Rumors on Mariners' George Kirby, Emerson Hancock and Luis Castillo Ahead of Deadline

In the midst of a disappointing 2026 season thus far, the Seattle Mariners are reportedly fielding interest in three of their top starting pitchers.

According to ESPN's Jeff Passan, multiple teams have been in talks with the Mariners regarding a trade for George Kirby, and the belief across the league is that he is available.

The Mariners have reportedly also listened to offers for Emerson Hancock and Luis Castillo ahead of Monday's trade deadline.

With three consecutive losses and eight in their past 10 games, the Mariners entered play on Saturday third in the American League West with a 53-58 record.

Despite being well under .500, the Mariners are only three games behind the first-place Houston Astros and three games out of a wild-card spot.

Because of that, it is far from a foregone conclusion that the Mariners will be deadline sellers, especially after they came within one win of the first World Series appearance in franchise history last season.

Starting pitching was a big reason why Seattle made it that far last season, and why the team was viewed as a World Series threat entering the 2026 campaign.

The 28-year-old Kirby has been a reliable performer this season despite the team's struggles, going 8-9 with a 3.98 ERA, 1.30 WHIP and 107 strikeouts in 120 innings over 20 starts.

A 2023 All-Star, Kirby owns a 3.65 ERA over his five MLB seasons, all of which have been spent in Seattle.

Hancock, 27, has been a revelation for the Mariners this season after posting a 4.81 ERA over his first three seasons.

In 20 starts this season, Hancock is 6-5 with a 3.26 ERA, 1.04 WHIP and 102 strikeouts over 110.1 innings.

Castillo is the most experienced and accomplished of the three Mariners pitchers who are potentially available.

The 33-year-old veteran is a three-time All-Star over his 10 MLB seasons with the Cincinnati Reds and Mariners, and he has a career ERA of 3.65 to go along with 87 wins.

This season has been a nightmare for Castillo, though, as he is just 3-9 and owns a career-worst 5.06 ERA and 1.40 WHIP. His strikeout rate of 7.8 per nine innings is also a career low, as he has punched out 86 batters in 99.2 innings.

Castillo is a battle-tested player with five career playoff starts to his credit, though, and it is possible a contending team could acquire him with the hope that a change of scenery will get him back on track.

Per Spotrac, Kirby is arbitration eligible in 2027 and 2028, Hancock is under team control through 2031, and Castillo is signed through 2028 at a salary of $21.6 million.

That means none of them would be rentals should a team acquire them, but it also suggests the Mariners are under no pressure to trade them, as there is no risk of losing them in free agency at the end of this season.