Grubauer was replaced by Pavel Francouz.
The injury appeared to occur early in the second period with Grubauer laying motionless on the ice for a couple of minutes.
The update after the game from Bednar was not promising either. Grubauer is not expected to attend practice on Sunday and Bednar said it was “bad news” that this was a tweak of a previous injury.
Grubauer, 28, has posted a 5-0-1 record with a 1.49 goals-against average and a .937 save percentage in six playoff starts for the Avalanche this season.
Francouz has started two games in this year’s playoffs, winning one and losing another, while registering a 1.02 GAA and a .958 SV%.