The Islanders lost their star and captain for the rest of the season because of an injury at the Sochi Games.
"John Tavares has an MCL and meniscus tear in his left knee," team spokesman Kimber Auerbach wrote in an email Thursday. "He will remain with Team Canada for the remainder of Olympics and return home after for further evaluation."
Tavares was hurt by a big hit along the boards by Latvia's Arturs Kulda in the second period of Canada's 2-1 victory Wednesday night. He writhed in pain on the ice for several seconds before skating to the bench and going to his team's dressing room.
"That's tough," Canadian teammate Jeff Carter said. "He was a big part of our team and obviously, you don't want to see anybody get hurt no matter who they are playing for. He was a great guy in the room."
Without Tavares, the defending Olympic champions will face the U.S. on Friday in the semifinals for a spot in the gold-medal game.
The Islanders are in last place in their division, nine points behind New Jersey, and are among the teams with the fewest points in the Eastern Conference.
Tavares has done his part to help his NHL team.
The 23-year-old forward is the league's third-leading scorer with 66 points in 59 games. He has never had significant injury problems in his five-season professional career, playing in 350 of a possible 354 games with New York.
Tavares is the latest player from the league to get injured in Russia, perhaps giving NHL owners another reason to want to keep their players home and playing with them during the 2018 Olympics.
The Florida Panthers sent just two players to Sochi, and both got banged up. Aleksander Barkov is expected to be out for about a month with a knee injury he got while playing for Finland. Tomas Kopecky is out indefinitely after getting elbowed in the head in a game for Slovakia.
Mats Zuccarello of the New York Rangers had a hand injury that ruled him out of Norway's finale against Russia.
Detroit Red Wings and Swedish captain Henrik Zetterberg aggravated a pre-existing back injury, which the Olympic team said was a herniated disk, after his Sochi Games opener and is out indefinitely.