David Backes started the scoring in a three-goal first period, Anders Nilsson made 19 saves in relief of an apparently injured Jake Allen, and the St. Louis Blues beat Colorado 5-1 on Sunday night as the Avalanche moved to the brink of postseason elimination.

Magnus Paajarvi, Colton Parayko and Alex Pietrangelo also scored for the Blues, who are chasing Dallas for the Central Division title and trying to stay ahead of Chicago. Troy Brouwer added an empty-netter with 2:55 remaining.

Matt Duchene scored late for the Avalanche, who maintained their slim playoff hopes with Minnesota losing to Winnipeg on Sunday. They trail the Wild by five points for the final Western Conference berth.

Both teams switched their starting goalie for the second period. Allen was replaced by Nilsson after sustaining an injury, Blues coach Ken Hitchcock told the NBC Sports broadcast in a bench interview.