Canadian supporters booed the US national anthem before Saturday’s 3-1 American round-robin victory at Montreal, setting the stage for an explosive start that saw three fights erupt in the game’s first nine seconds.

More fist-flying mayhem is possible and another electric atmosphere is assured Thursday at Boston when the Canadians face their bitter border rivals for the championship.

“It just happens to be against the team that beat us after the fireworks that went off on Saturday night,” Canada coach Jon Cooper said. “So I think it should be a pretty good made-for-TV event.”

US coach Mike Sullivan expects another heated atmosphere.

“I would anticipate the next one will be every bit as competitive if not more,” he said. “The way that game was played, with the emotional investment on both sides, it’s just such an indication of how much these guys care and what this means to them.

“It will be an incredible atmosphere. I know our guys are excited. There’s a lot of pride at stake and it will be a hard-fought battle.”

In addition to the kind of hype usually reserved for heavyweight boxing promotions, Thursday’s grudge match also drips with political intrigue.

Booing of “The Star-Spangled Banner” has become commonplace at sports venues throughout Canada following US President Donald Trump’s threat to impose tariffs on Canadian goods.

Trump has also incensed Canadians with repeated calls for their country to become the USA’s “51st state”, while routinely referring to outgoing Canada Prime Minister Justin Trudeau as “Governor Trudeau.”

US team general manager Bill Guerin told Fox News that recent political tensions have heightened what was already a heated rivalry.