The Tigers rebounded from a 13-3 loss on Tuesday to win two of three against the Mariners.
Porcello (1-2) moved to 3-0 lifetime against Seattle, allowing just one run on four hits and a walk while striking out six. Ryan Perry and Joaquin Benoit combined to pitch 1 1/3 scoreless innings and Jose Valverde earned his fourth save despite surrendering a solo homer to Adam Kennedy in the ninth.
Ryan Raburn had a solo homer for Detroit in the first inning and scored the eventual game-winning run on Brennan Boesch’s single in the fifth.
Erik Bedard (0-4) continued to struggle for the Mariners, taking the loss after giving up three runs in five innings. He surrendered five hits and five walks, striking out two.