The knee injury is similar to the sprained MCL sustained by Toronto forward Zach Hyman on April 18, Maple Leafs general manager Kyle Dubas said Saturday.
"It will be a minimum of two weeks on that, but obviously our primary concern is the concussion and making sure he returns to full health," Dubas said.
Hyman returned from his injury to play Thursday. Dubas said it's unknown how long Tavares will be out with the concussion.
"The knee injury you can give a timeline on, but the head injury and concussion, it's very difficult to place a timeline on when someone is going to return from that," Dubas said. "We handle those in a very conservative nature and handle them very sensitively. We will follow the protocols to a T on that. We can't replace that element with John and cannot repair it. We are keeping in mind he has a young family and there is an onus on us to protect him and his future in that regard."
Tavares was cleared of all structural damage to his head, neck and spine after a CT scan and MRI on Thursday, Dubas said.
"It was a major concern at the time of incident, so we are thankful for that," Dubas said. "John was admitted to the hospital overnight for observation and was discharged yesterday morning and returned home with Dr. [Noah] Foreman and has been with his family since then and under the close watch and care of Dr. Foreman."
Toronto's captain was injured when he fell near the blue line after being checked by Canadiens defenseman Ben Chiarot and then was hit in the face by the left knee of Montreal forward Corey Perry with 9:31 remaining in the first period. Tavares was taken from the ice on a stretcher and examined by the St. Michael's Hospital neurosurgical team and the Maple Leafs medical director.
After staying overnight, Tavares was home Friday under the supervision of Maple Leafs doctors.
"The support I've felt from last night cannot be put into words. I'm thankful to share that I'm back home and recovering," Tavares tweeted Friday. "Thank you to my family, friends, teammates, the Maple Leafs organization, Leafs Nation and the hockey community for being by my side. Also, thank you to both medical teams, emergency services and everyone at St. Mike's hospital for their exceptional care to help me get back on my feet.
"I look forward to when I can wear the Maple Leaf on my chest again. Until then I'll be cheering on the boys along with Leafs Nation as we compete in the Stanley Cup Playoffs."
Toronto evened the best-of-7 series with a 5-1 win Saturday. Game 3 is at Montreal on Monday.
"All things considered, John's doing very well," Maple Leafs coach Sheldon Keefe said Saturday. "Talking to him, he's very thankful for the care he got. He knows it was a scary situation and he's appreciative of the support and concern people have for him."
Perry said the collision was an accident.
"He got hit and I was coming out of the zone," Perry said after Montreal's 2-1 win. "He fell and I tried to jump over him and unfortunately I caught my knee on his head. I don't know what else to do there. I know Johnny pretty well. I just hope he is OK."
Keefe said it one of the tougher moments he's had in hockey.
"To be honest, it was difficult," he said. "I've experienced a lot of different things, a lot of tough injuries and stuff like that in my time as a player and as a coach. In an empty building like that, it was probably the most uncomfortable situation that I've been a part of on the ice. It was really tough to get through. Our players were rattled and concerned. I was obviously very concerned as well. Happy to hear that things are settling down and all of that, but it was a very tough moment."
