Swanson began the season at the Mariners' alternate training site even though he posted a 2.84 ERA and 0.63 WHIP in 6.1 innings this spring. However, he'll rejoin the major-league bullpen after Anthony Misiewicz was placed on the injured list for an unspecified reason Monday. Swanson gave up 11 runs in 7.2 innings across nine relief appearances for Seattle last year and will presumably serve in a low-leverage role in 2021.
