It's been a decades-long tradition in North America, but a Canadian professor of sport management says it might be time to re-examine the legitimacy of national anthems being played before games.

The 4 Nations Face-off's marquee matchup took an ugly turn before the puck even dropped on Saturday. Ahead of the long-awaited game between Team USA and Team Canada, fans booed the U.S. national anthem, continuing a recent trend of Canadians expressing their displeasure with the Americans.

Fans in Montreal continued to boo the American national anthem and a string of fights followed in a Team USA win over Canada in Saturday night’s 4 Nations Face-Off game.