The 30-year-old goalie was injured Tuesday when he was struck in the mask on a shot by Philadelphia Flyers defenseman Shayne Gostisbehere in the second period of a 3-2 overtime loss. Price remained in the game.
"It's been diagnosed as a concussion," Canadiens coach Claude Julien said Thursday. "He'll continue to get evaluated on a daily basis. You never know with concussions, it could be short term, it could be long term. We'll see."
Price, who is 15-22-6 with a 2.98 goals-against average and .904 save percentage, is 2-8-4 with an .889 save percentage in his past 14 games. He missed 10 games from Nov. 4-22 with a lower-body injury.
Antti Niemi will start in net for Montreal against the New York Rangers on Thursday (7:30 p.m. ET; RDS, TSN2, MSG2, NHL.TV).
The Canadiens (22-29-8) are 13 points behind the Columbus Blue Jackets for the second wild card into the Stanley Cup Playoffs from the Eastern Conference.
Goalie Charlie Lindgren was recalled on an emergency basis from Laval of the American Hockey League on Wednesday.
