Josiah Morra of Toronto scored two tries, the second with 24 seconds left on the clock, to lead Canada's men to a rugby sevens semifinal against Great Britain on Sunday in Edmonton.
Brennig Prevost made the conversion from a distance at Commonwealth Stadium to cement a 14-12 victory by the sixth-seeded Canadians over No. 4 Ireland.
Canada will play the Brits at 3:20 p.m. ET after dropping a 31-5 quarter-final decision to them at last week's World Rugby Sevens Series event in Vancouver.
In Sunday's match, Morra opened the scoring at the three-minute mark with his third try of the tourney when he straight-armed an Ireland defender on the way to the try line.
Jordan Conroy answered one minute 35 seconds later with his third try of the weekend competition.
Early in the second half, Ireland took advantage of Canada being down a man after Andrew Coe was sent off the pitch with a yellow card.
Aaron O'Sullivan gave the Irish a 12-7 lead, but Sean Cribbin missed the convert.
Canada's women face the United States in semifinal play at 2:04 p.m. ET after a 40-12 drubbing of Mexico followed draws with the Americans (26-26) and Great Britain (7-7) on Saturday.
The women's competition features just four teams: Canada, Britain, the U.S. and Mexico.
The "Fast Four" competition format sees the teams play each other before the top two decide the gold and the other two meet for third.
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