Evan Longoria grounded a go-ahead, two-run single into left field with one out in the seventh inning Sunday afternoon, propelling the San Francisco Giants to a 5-4 victory over the host Oakland Athletics and a two-game sweep of their interleague series. After Oakland's Mark Canha had hit two home runs off San Francisco starter Logan Webb, five Giants relievers combined on 4 1/3 innings of one-hit, shutout relief, allowing the Giants to capture the season series 3-1 in the annual rivalry. Neither team had scored since Canha's second home run, his 22nd of the season, had given the A's a 4-3 lead in the fourth before Oakland first baseman Matt Olson fumbled Brandon Crawford's grounder to open the gates in the seventh.