Artturi Lehkonen and Cale Makar each had a goal and an assist, and Nathan MacKinnon had two assists for Avalanche, the No. 3 seed from the Central Division. Alexandar Georgiev made 25 saves.
Nate Schmidt scored for the Jets, who are the No. 2 seed from the Central. Connor Hellebuyck allowed four goals on 30 shots before being replaced by Laurent Brossoit at the start of the third period. Brossoit made four saves.
Game 5 of the best-of-7 series will be in Winnipeg on Tuesday (9:30 p.m. ET; CBC, TVAS, SNW, ALT, ESPN).
Lehkonen scored to make it 1-0 Colorado when he one-timed Casey Mittelstadt’s backhand pass from behind the net to the right hash mark at 8:10 of the first period.
Schmidt tied the game at one at 13:56, skating into a pass from Mason Appleton above the right circle and scoring on a wrist shot top shelf far side. The Avalanche challenged the play for offside, but video review upheld the original call.
Nichushkin scored a power-play goal to make it 2-1 at 11:36 of the second period when he redirected Cale Makar’s initial shot downward and through Hellebuyck.
Makar extended the lead to 3-1 at 15:03 with a wrist shot from above the right dot that went far side. He started the rush behind his own net and took it coast to coast before the shot.
Nichushkin made it 4-1 with a power-play goal at 19:36, snapping the crossing pass from Lehkonen into the open net from atop the crease.
Nichushkin scored into the empty net at 19:47 of the third period for the 5-1 final.
Jets forward Vladislav Namestnikov left the game at 6:57 of the third period after Schmidt’s shot from the blue line hit him in the face.
