The Mariners signed Dobnak to a minor-league contract with an invitation to spring training Tuesday, Jeff Passan of ESPN.com reports.
Dobnak became a free agent last week after the Tigers declined his option for 2026, and he's now headed to the Pacific Northwest. The 30-year-old spent nearly all of 2025 at the Triple-A level, holding a 5.84 ERA over 18 starts and eight relief appearances. Dobnak will likely begin the 2026 season in the rotation at Triple-A Tacoma.