Hejuk's goal off an O'Reilly assist less than 7 minutes into the game gave the Avalanche the lead for good at 1-0.
Kyle Quincey and Chuck Kobasew followed with second-period tallies and Hejduk added a power-play goal -- with another assist from O'Reilly -- in the final frame for the Avalanche, who won for the eighth time in nine games.
Jean-Sebastien Giguere made 18 stops to earn the victory.
Anaheim's Jonas Hiller made 22 saves.
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