Tanner Swanson's Role in Seattle's
The Mariners have brought in Swanson, an experienced catching-development specialist, as bench coach under newly appointed manager Jason Kanzler. His hiring strengthens the team’s coaching staff, particularly with the expertise he gained while developing catchers for the New York Yankees.
Tanner spent seven seasons with the Yankees, from 2020 to 2026, initially serving as the team's director of catching. In 2024, he also took on the responsibilities of Major League field coordinator. During his tenure in New York, the club's backstops delivered a strong stretch of defensive performances.
This background helps explain Seattle's decision to hire him. Catcher framing is the ability to receive pitches in a way that can affect an umpire's strike-or-ball decision, especially on borderline pitches near the edges of the strike zone. MLB's Statcast system tracks this skill through framing runs.
His expertise could help the Mariners improve their catching fundamentals, defensive preparation and communication between catchers and pitchers. Cal Raleigh, could benefit from his guidance. Still, any progress in his defensive performance will depend on his own execution and development.
Swanson's role with Seattle will extend beyond working with the team's backstops. He will work closely with Kanzler and the rest of the staff on game preparation, communication and strategic decisions. His previous background as the Yankees' Major League field coordinator also gives him a background that fits the wider responsibilities of the position.
Tanner's hiring gives Mariners with extensive experience in one of baseball's increasingly specialized areas of defense. His work with the New York provides a solid basis for optimism, but bringing similar results to the Seattle will take time and depend on how well his leadership translates on the field.