The Mariners claimed Danner off waivers from the Blue Jays on Wednesday, Scott Mitchell of TSN.ca reports.
Danner made one appearance for the Blue Jays in 2023 before spending most of the 2024 campaign at Triple-A Buffalo, holding a 3.15 ERA and 34:13 K:BB over 34.1 frames. He'll compete for a bullpen job in Seattle but has minor-league options remaining.