Volquez (1-2) notched his first win in seven starts for the Padres, surrendering a pair of runs on five hits while overcoming four walks and striking out five.
Yonder Alonso delivered a two-run single in the first inning and Orlando Hudson scored the eventual game-winner on a wild pitch in the second.
Colorado's Drew Pomeranz (0-2) absorbed the loss, allowing three runs on five hits in a three-inning start. The left-hander also cracked a solo homer.
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