While the rest of the team practised Tuesday, St-Gelais was having tests to determine the severity of a concussion suffered at a World Cup meet last weekend in Calgary.
The results will determine whether the double silver medallist from the 2010 Winter Olympics will be able to skate at the season's second World Cup beginning Friday at the Maurice Richard Arena, which is the training base for St-Gelais and most of the Canadian team.
''She's having tests, but from what I see from her, she'll be back on the ice (Wednesday),'' said Hamelin.
St-Gelais lost an edge on a turn in Calgary, hit the protective padding that surrounds the track and hit her head on the ice.
Team director Yves Hamelin, Charles' father, said she had headaches after the incident but was symptom-free on Tuesday morning before going for tests.
Concussions are one of the hazards of short-track, where spills are common as competitors race four at a time at close quarters around a tight oval. Especially on the super-fast ice in Calgary
Even with St-Gelais' mishap, Canada came away with four silver and two bronze medals from the opening stop on the circuit and hope to do even better in Montreal.
The Calgary meet saw Wang Meng return to competition after a long layoff to win the women's 500-metre race. It also saw South Korea's rising star, Shim Suk-Hee, set a world record while taking the women's 1,500 metres.
The Americans were also impressive, especially J.R. Celski who was first in the 500 metres and third in the 1,000.
And it saw Russia take another step in its bid to become a power in the sport in time for the 2014 Games on home ice in Sochi. Vladimir Grigorev took the first of two men's 1,000-metre races while the Russian men came second in the relay.
Yves Hamelin said Canada may have done better, but women's stars Valerie Maltais and Marie-Eve Drolet both fell during events in which they were expected to win medals.
''As I always say, in short-track the stars are never totally aligned,'' he said. ''There's always something happening that we don't want to see.
''This week we have two 500-metre races, which is a distance where our athletes react well, so it should be good racing.''
St-Gelais does not have much history with concussions and neither does Charles Hamelin, who said he has had two in 20 years of skating.
But concussions are part of the sport just like nasty skate cuts that happen when two or three all crash into the padding together.
At the trials for the current round of World Cup meets, there were four reported concussions, including one to team veteran Marie-Eve Drolet. National development team member Vanessa Belanger-Marceau is still out of action after experiencing concussion symptoms.
''It's something that happens pretty frequently because of the speed of the athletes and the force of impact,'' said Yves Hamelin. ''Depending on their position, most of the time there is no issue.
''But sometimes they have no time to reposition themselves and avoid hitting their head first. We see it too often, I'd say.''
Drolet was back on the ice 10 days after her concussion and feels fine. She was second in a 1,000-metre event in Calgary, on the same ice where she hit her head at the trials.
''It was in the 500 semifinal and someone hit a block (lane marker) just in front of me,'' she recalled. ''The block came into my space and made me fall.
''I fell at the end of the corner. I was going full speed and I just hit the boards.''
Now Drolet is only concerned about winning, and beating Shim, who won at the 1,000 and 1,500-metre distances in Calgary.
''She's something,'' Drolet said. ''She's taller than all the other Koreans.
''She set a world record. I like it. It makes the race faster. That makes it a bit better for me because I have endurance and I can just try to beat them at the end.''