REPORT: San Francisco Giants Inquired About All-Star Right-Hander in Offseason

Last offseason, the San Francisco Giants turned to the Seattle Mariners for a trade to strengthen their starting rotation’s future. This offseason, they reportedly explored a similar move.

According to The San Francisco Chronicle’s Susan Slusser, the Giants were among several teams that inquired about Mariners pitcher. While He remains in Seattle, he was a popular name in trade discussions as teams, including the Giants, sought to bolster their rotations.

Last year, San Francisco acquired left-hander Robbie Ray from the Mariners in exchange for Mitch Haniger, Anthony DeSclafani, and cash considerations. Ray, the 2021 AL Cy Young winner, was recovering from Tommy John surgery at the time.

He returned in July, posting a 3-2 record with a 4.70 ERA in seven starts. The Giants’ gamble on Ray paid off, as he exercised his player option for 2025 and is expected to be their No. 2 or No. 3 starter.

Castillo, unlike Ray, is fully healthy and under contract at a controlled but significant cost. He is signed through 2027 at roughly $24 million per season, with a $25 million vesting option for 2028 before hitting free agency in 2029.

However, a potential hurdle in any trade is Castillo’s no-trade clause, which would require his approval for a deal to go through. It’s unclear if the Giants’ inquiry reached that stage.

A three-time All-Star, Castillo is a key part of one of MLB’s top rotations. The Mariners likely would have only moved him to address their offensive needs. In 2023, he finished fourth in AL Cy Young voting, going 14-9 with a 3.34 ERA across 33 starts, striking out 219 batters while issuing 56 walks over 197 innings.

For 2025, the Giants have named Logan Webb their Opening Day starter for the fourth consecutive year. Ray will be in the rotation alongside three-time Cy Young winner Justin Verlander, who joined on a one-year deal.

The remaining rotation spots will be decided among Jordan Hicks, Kyle Harrison, Hayden Birdsong, Tristan Beck, Landen Roupp, and Keaton Winn.