The Red Sox had been held scoreless on two hits over seven innings by Tigers starter Max Scherzer and were trailing 5-1 entering the eighth when they began an improbable comeback against the Detroit bullpen.
The Tigers brought in closer Joaquin Benoit and Ortiz greeted him by lining his first pitch over the right-field wall for a grand slam. Tigers outfielder Torii Hunter careened over the fence and into the Red Sox bullpen trying to make the catch.
Gomes went to third on a wild pitch and scored the game-winning run on Jarrod Saltalamacchia's single past a diving Iglesias.
Koji Uehara (1-0) earned the win for the Red Sox, who evened the ALCS at 1-1 with the wild comeback.
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