Belt went 3-for-4 and doubled in the tying run in the eighth before Perez singled to right field off Dale Thayer (0-3) to bring Belt in with the deciding run.
Gregor Blanco and Buster Posey also chalked up RBI for the Giants, who outhit the Padres 13-9. Jean Machi (2-0) pitched 1 /3 of an inning for the win in relief of Matt Cain. Cain turned in a yeoman start, allowing two runs on six hits and striking out 10 in seven innings.
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