The southpaw was backed by a strong offensive performance. Haniger went 4-for-5 with a pair of RBIs and was a triple short of the cycle; Cano went 4-for-5 with four RBIs; Ruiz went 2-for-3 with a double; and Jean Segura went 3-for-4 with a walk.
Nelson Cruz, Yonder Alonso and Ben Gamel drove in runs in the five-run eighth inning.
The Mariners pulled within 2 1/2 games of the Twins for the second American League Wild Card spot after Minnesota fell to Kansas City, 5-4, on Sunday.
The A's losing skid was extended to six games.