Carlos Gonzalez supplied three hits with an RBI and Josh Rutledge scored three times for Colorado, which clinched its three-game road series.
Jhoulys Chacin (2-0) notched the win, allowing two runs on four hits and two walks over five innings. The right-hander recorded three strikeouts.
Padres starter Edinson Volquez (0-3) was tagged for seven runs (six earned) on six hits in a 3 1/3-inning effort.
Everth Cabrera went 4-for-5 with a homer and two RBI as San Diego fell to 2-9 beginning the season.
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