Canadian pairs skater Bryce Davison injured his knee while attempting triple loops in training, according to a source who saw the injury occur.
Davison was in a monitoring session with coach Petra Burka in Toronto last week when he started trying the triples.
The source told CBCSports.ca that he went up for a jump, popped it into a single, came down a bit awkwardly on his landing knee and was in immediate pain.
How Davison was injured wasn't officially disclosed by Skate Canada. He had an MRI on the knee on Friday and is expecting results from it Monday night or Tuesday morning.
He and partner Jessica Dubé were favoured to win the Skate Canada International this weekend in Kingston, Ont., but had to withdraw due to the injury.
The setback will also cost Davison, from Huntsville, Ont., and Dubé, from St-Cyrille-de-Wendover, Que., a spot in the season-ending Grand Prix final in Beijing in early December.
"This is obviously not the way we wanted to start our season. Our training had been going really well, and we were looking forward to competing at home at Skate Canada International," Davison said in a statement on Monday.
Dubé and Davison won bronze at the 2007-08 world championships and were sixth at the Vancouver Olympics. They will be replaced at Skate Canada by Kirsten Moore-Towers and Dylan Moscovitch of Waterloo, Ont.
The defending Canadian champions are still scheduled to compete at the Rostelecom Cup in Russia next month.
Olympic ice dance champions Tessa Virtue and Scott Moir will also miss Skate Canada after Virtue underwent surgery on both legs to ease chronic pain in her shins.