PITTSBURGH (AP) - Pedro Alvarez's two-run double sparked a seventh-inning rally and the Pittsburgh Pirates beat the Detroit Tigers 5-3 on Wednesday night. Travis Snider added an RBI double and Jordy Mercer laid down a perfect suicide squeeze as the Pirates erupted late against Anibal Sanchez (5-5) and scored four times. Miguel Cabrera hit his 15th homer of the season for Detroit and Andy Dirks had an RBI double, but that couldn't prevent the Tigers from falling to Pittsburgh for the second straight night. Bryan Morris (2-2) picked up the win in relief of A.J. Burnett. Jason Grilli pitched the ninth for his major league-leading 22nd save. Sanchez cruised through the first six innings, surrendering only a solo home run to Neil Walker. Things unraveled in the seventh as the Pirates batted around.