SAN FRANCISCO (CBS/AP) -- Hunter Pence hit a grand slam as part of an eight-run fourth inning against former All-Star Cole Hamels, and the San Francisco Giants beat the Philadelphia Phillies 15-2 on Friday night.

Joe Panik had four hits, including a two-run homer, and drove in three runs. Justin Maxwell, who also had four hits, tripled and doubled in runs and was a home run shy of the cycle. Matt Duffy recorded a career-high four hits as the Giants accumulated 22 hits, their most in AT&T Park history.

All-Star Madison Bumgarner (9-5) went 5 2-3 innings, allowing two runs on eight hits. He failed to finish six innings in back-to-back starts for the first time this season.

Bumgarner and Hamels were the first former World Series MVPs to meet in four years.

Hamels (5-7) got the first out of the fourth and then surrendered seven hits and walked a batter before Jake Diekman came in to finish the inning.

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