The Avalanche now lead the series 3-1 and could eliminate their rival in Winnipeg on Tuesday.
Artturi Lehkonen and Cale Makar also scored for the Avalanche. Nathan MacKinnon had two assists.
Nate Schmidt found the back of the net in the loss.
Jets defenseman Brenden Dillon of the Jets missed Sunday’s game with a left hand injury. Logan Stanley replaced Dillon in the Jets lineup.
Dillon suffered a nasty cut from a skate blade during a scrimmage late in Game 3 Friday, which the Jets lost 6-2.
The Jets also brought in speedy forward Axel Jonsson-Fjallby to replace David Gustafsson.
The Avalanche started the game strong, firing nine shots on net from Connor Hellebuyck in the first seven minutes of play.
Lehkonen opened the scoring with a wrist shot at 8:10 in the first period.
Schmidt tied the score by beating Alexandar Georgiev with a shot into the top of the net, from the shield side, at 13:56 of play.
Nichushkin scored his second goal of the game with 24 seconds left in the second period, to make it 4-1. It was a fifth goal for the striker in this series.
Laurent Brossoit replaced Hellebuyck in front of the Jets net after the second period.
Vladislav Namestnikov left the game midway through the third period after receiving a slapshot to the side of the head.
