With time winding down in regulation, Legwand launched a shot at Jean-Sebastien Giguere from in close. The Avalanche goaltender made the initial save, but Legwand was able to swat in the rebound for the decisive tally.
The victory boosted Nashville into a tie with St. Louis for the eighth and final Western Conference playoff spot.
Pekka Rinne turned aside 25 shots in the win.
Matt Duchene scored and Giguere finished with 35 saves for Colorado.
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