The netminder was pulled late in the third period, and immediately went to the team's dressing room.
Good news appeared after the game as Varlamov was seen in high spirits with his team after their win reports Rick Sadowski of NHL.com.
He was replaced by Reto Berra.
The Avalanche won the contest 3-2.
Varlamov was 21-17-7 with a 2.59 goals-against average entering Sunday's game.