SEATTLE – The Mariners today announced their minor league coaching staffs for the 2026 season.
“We are excited and proud to announce our affiliate staffs for the upcoming season,” said Mariners Director of Player Development Justin Toole. “From our ACL and DSL teams all the way up to Tacoma, we are confident that we have great fits to lead one of the best farm systems in baseball.”
TRIPLE-A TACOMA RAINIERS
Manager John Russell returns for his fourth season as Rainiers manager. Tacoma went 86-64 last season and won its league’s second-half title, the fourth consecutive year the Rainiers have finished above .500 under Russell. Eric Farris returns as bench coach, his eighth season in the Mariners organization and his fourth with Tacoma. Seth Mejias-Brean joins Tacoma as hitting coach, his third consecutive year moving up in the organization after serving the same role for High-A Everett in 2024 and Double-A Arkansas in 2025.
Pitching coach Mike McCarthy joins the Mariners organization after serving as a coach in the Athletics and Atlanta Braves systems since 2023. McCarthy has also served as a coach in the Minnesota Twins and San Diego Padres organizations. Corey Measner returns as strength and conditioning coach, Aric Quinney returns as athletic trainer, and Amanda Lee returns as athletic trainer/assistant minor league athletic training coordinator.
DOUBLE-A ARKANSAS TRAVELERS
Manager Rich Thompson joins the Mariners organization as Travelers manager after serving as athletic director and head baseball coach at National Park College in Arkansas. Thompson is originally from Sydney, Australia and pitched 6 seasons in the Major Leagues with the Los Angeles Angels (2007-12) and Athletics (2012), posting a 4.21 ERA with 105 strikeouts in 104.2 innings pitched. Thompson pitched for the Arkansas Travelers for two seasons from 2006-07.
Jose Umbria returns as bench coach, while Cameron Ming returns as pitching coach. Jordan Cowan joins Arkansas as hitting coach after serving the same role for High-A Everett in each of the last two seasons. Kyle Briggs will serve as strength and conditioning coach and Dan Laberry will serve as athletic trainer.
HIGH-A EVERETT AQUASOX
Manager Ryan Scott returns to Everett, managing the AquaSox for two seasons from 2023-24. Scott managed Double-A Arkansas last season. Bench coach Logan Moore joins the Mariners organization after serving as a catcher in the Philadelphia Phillies organization from 2011-21.
Chase Miller will serve as hitting coach and Bryan Pall pitching coach, with the pair serving in the same roles for the ACL Mariners in 2025. Max Miller returns as strength and conditioning coach and Blake Wooten will serve as athletic trainer.
CLASS-A INLAND EMPIRE 66ERS
The Mariners welcome a new Class-A, California League affiliate to the organization in 2026: the Inland Empire 66ers. The 66ers, who play their home games at San Manuel Stadium in San Bernardino, California, served as the Los Angeles Angels Triple-A affiliate for the last 15 seasons (2011-25). Inland Empire had previously been a Mariners affiliate for 14 seasons across two stints: 1987-94 and 2001-06.
Luis Caballero will manage the 66ers in their return to the organization, his second season as Seattle’s Class-A manager after leading the Modesto Nuts in 2025. Caballero will be in his 11th season in the Mariners organization. Former minor league catcher Josh Morgan will serve as bench coach for Caballero for the second straight season. Former pitcher Sam Delaplane joins Inland Empire as pitching coach, his first year as a coach. Delaplane was selected by Seattle in the 23rd round of the 2017 MLB First-Year Player Draft out of Eastern Michigan University, and made it up to Triple-A Tacoma. Luke Carlson will serve as strength and conditioning coach, while Bryanna Brown will serve as athletic trainer. Any additional hires to the Inland Empire staff will be announced at a later date.
ARIZONA COMPLEX LEAGUE MARINERS
Hecmart Nieves will serve as ACL Mariners manager, with Chase Wullenweber as bench coach and Tanner Gordon as pitching coach. George M. Bell, the son of 1987 AL MVP George Bell, has been hired as the ACL Mariners hitting coach. Sergio Plasencia will serve as return to play coach, while Quinten Arellano will serve as strength and conditioning coach. Cameron Werme returns as athletic trainer, while Randy Roetter returns as athletic trainer. Roetter enters his 39th season working in the Mariners organization.
DOMINICAN SUMMER LEAGUE MARINERS
Luis Matias will serve as DSL Mariners manager for the second straight year. He has served the organization in a variety of roles, starting as a video coordinator in 2015. Bench coach Guady Jabalera enters his eighth season as a coach for the DSL Mariners, while Jose Amancio returns as pitching coach. Angus Stayte will serve as hitting coach, Jesus Galindo outfield/baserunning coach, Ramire Cleto head strength and conditioning coach, and Alfredo Alcantara strength and conditioning coach.
Ivan Mercedes will serve as a mental performance coach, Humberto Figueroa athletic trainer, Ronaldo De La Cruz D.R. Academy rehab therapist, Walkyria Torres coordinator, D.R. Education, and Estefany Henriquez coordinator, D.R. baseball operations.