The World Junior Championship, an annual showcase of the next generation of hockey stars, which was already underway in Canada, was canceled on Wednesday as the rapid spread of the Omicron variant of the coronavirus continued to wreak havoc on the sports world.
The International Ice Hockey Federation, the sport’s global governing body, said it was scrapping the tournament after a player on the Russian national team tested positive for the virus, which would have necessitated the cancellation of the third game in two days, between Russia and Slovakia on Wednesday.
Two previous games — between Switzerland and the United States and between Finland and the Czech Republic — had already been canceled because of positive cases.
The cancellation was an ominous sign for sports leagues, including the N.H.L. and the N.B.A., which have been struggling to maintain schedules amid a steep surge in cases driven by the convergence of the Omicron and Delta variants.
On Tuesday, U.S.A. Hockey said the final two games of the women’s national team’s My Why Tour, which had been set for Jan. 3 and Jan. 6 in Alberta, Canada, had been canceled, less than a month before the team was scheduled to leave for the 2022 Winter Olympics in Beijing.
The World Juniors, which was also being held in Alberta, is a beloved post-Christmas tradition in Canada, transfixing fans in the country, which has historically dominated the event.
The United States won last year’s tournament, which features some of the best men’s hockey players under 20, who train for years to reach the event and are considered top prospects for the N.H.L.
Over the past decade, the tournament’s most valuable players have included the New York Rangers’ first overall pick Alexis Lafreniére (2020), Filip Forsberg of the Nashville Predators (2014) and John Gibson of the Anaheim Ducks (2013).
Luc Tardif, the president of the International Ice Hockey Federation, said the organization had begun the tournament “with full confidence” in the protocols that had been put in place, but then had to readjust them as cases surged. The protocols included daily testing and a team quarantine requirement when positive cases were confirmed.
“Unfortunately, this was not enough,” Mr. Tardif said in a statement. “We now have to take some time and focus on getting all players and team staff back home safely.”
John Vanbiesbrouck, general manager of the United States National Junior Team, said he was proud of the team and would work to ensure they get home safely.
“Our hearts go out to the players and staff of not just our country,” he said in a statement, “but every nation, who have worked so hard, and sacrificed so much, to get to this point.”