Giants 5, Athletics 2: All-Star Hunter Pence went 2-for-5 with a homer and two RBIs while Matt Cain tossed six solid innings as host San Francisco halted Oakland's six-game winning streak.Joe Panik and Brandon Crawford each recorded two hits and scored once while Buster Posey plated a run for the Giants, who won for just the fifth time in 16 contests. Cain (2-7) halted his seven-start winless streak by limiting Oakland to two runs on five hits and two walks, and Santiago Casilla worked a perfect ninth for his fourth save.Stephen Vogt went 2-for-2 with a homer and Jed Lowrie notched two hits and an RBI for the Athletics, who have lost 13 of their last 15 games in San Francisco. Jason Hammel (8-6) fell to 0-3 lifetime against the Giants as he yielded three runs - two earned - and six hits over five frames in his Oakland debut.San Francisco struck first as Gregor Blanco drew a one-out walk in the second inning and scored when Oakland left fielder Yoenis Cespedes was unable to come up with Panik's single cleanly. Posey doubled the lead in the third with an RBI single, but Vogt halved the deficit by leading off the fourth with his third blast.Pence made it 3-1 in the bottom of the frame with a two-out solo shot, but Lowrie delivered a run-scoring single in the sixth to again make it a one-run game. The Giants padded their lead in their half of the inning as Pence plated Panik with an infield single and Crawford raced home on a wild pitch by Eric O'Flaherty.GAME NOTEBOOK: Oakland fell to 9-2 in interleague games this season while San Francisco improved to 7-4. ... Hammel has allowed two earned runs in each of his last four starts but is just 2-2 in that span. ... The Giants scored a total of one run in two losses at Oakland this week.