Senators general manager Pierre Dorion updated Forsberg’s status after the team’s practice on Sunday.
Forsberg was injured late in the third period when Senators defenceman Travis Hamonic pushed Oilers winger Zach Hyman on top of the goaltender during a goalmouth scramble.
Forsberg had to be removed from the ice on a stretcher.
The 30-year-old Forsberg has an 11-11-2 record and a .902 save percentage in 28 appearances this season.
The Senators also said defenceman Jake Sanderson will miss at least two weeks with an upper-body injury sustained in the 6-3 loss to Edmonton.
Sanderson left the game after taking a hit from Oilers defenceman Vincent Desharnais in the third period.
The rookie has four goals and 18 assists in 52 games.