Jonathan Drouin of the Halifax Mooseheads suffered concussion-like symptoms after being hit in Friday's game against the Quebec Remparts in the Quebec Major Junior Hockey League.
Drouin was hit hard into the boards from behind by Remparts winger Adam Erne in the first period and did not return. He skated off the ice on his own.
Erne received a major for checking from behind and a game misconduct.
A serious injury would have world junior championship implications for both Drouin and Team Canada. The 18-year-old Ste. Agathe, Que., native is among 25 invitees to Canada's selection camp, which begins Thursday in Toronto.
Drouin played in last year's tournament on a Canadian squats that finished fourth in Ufa, Russia.
Drouin, who was taken third overall by the Tampa Bay Lightning at last summer's NHL Draft, sits second in QMJHL scoring with 17 goals and 33 assists through 23 games.