Ismael Kone's serious-looking injury left Canada manager Jesse Marsch in tears and overshadowed their first-ever World Cup finals win as they thrashed nine-man Qatar 6-0.
With the co-hosts already leading 3-0 in Vancouver and with a man advantage, Qatar's Assim Omer Madibo and Kone both challenged for the ball, resulting in a lengthy stoppage and the Canadian being stretchered off.
Madibo was originally shown a yellow card, but it was upgraded to a red after a video assistant referee (VAR) intervention.
But with his name being chanted by the Canadian supporters, ex-Watford midfielder Kone was able to sit up and wave as he was carried around the side of the pitch on a stretcher while inhaling painkillers.
Canada are now likely to reach the knockout rounds, but the injury to Kone is a huge blow to their prospects of a run beyond the last 32.
The horrific injury marred what was otherwise a historic occasion for Canada.
Cyle Larin opened the scoring with a poacher's finish in the 16th minute, netting his second in as many games, before Jonathan David scored the first of his hat-trick 13 minutes later.
Qatar were then shown the first of their two red cards as Homam El Amin was sent off for a professional foul on Tajon Buchanan in the 33rd minute.
David netted his second in first-half added time.
Kone's injury overshadowed the second half: When Nathan Saliba curled in a free-kick to make it 4-0 in the 63rd minute, he held up the injured midfielder's shirt - a gesture that was met by huge cheers from the crowd.
Canada added a fifth with 15 minutes remaining as Mohammad Al Mannai sliced Jacob Shaffelburg's effort into his own goal.
David rounded off a superb hat-trick in stoppage time by latching on to Buchanan's effort before driving beyond Mahmoud Abunada.
Victory by a six-goal margin means Canada sit top of group B - level on points with Switzerland, but three goals better off.


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