The Associated Press The United States’ Matt Boldy (12) celebrates his goal past Finland goaltender Juuse Saros during the second period in Montreal on Thursday.

MONTREAL — Brady and Matthew Tkachuk each scored twice, and the brothers had a handful of big hits to help the United States beat Finland 6-1 on Thursday night in each team’s opening game at the 4 Nations Face-Off, a physical showdown played with edge throughout.

Everyone was finishing checks, including Jack Eichel dumping Finnish captain Aleksander Barkov into the U.S. bench. Brady Tkachuk bowled over 6-foot-6 Niko Mikkola with one of his game-high eight hits, and Matthew Tkachuk gave Patrik Laine an earful before a faceoff as the Americans began to take over.

The scoreboard made it look like more of a rout than it was for the first two periods, when quality chances were at a premium and space on the ice was hard to find. Matt Boldy scored the go-ahead goal on a textbook deflection of Minnesota Wild teammate Brock Faber’s shot late in the second, then the floodgates opened early in the third.

Many fans hadn’t even returned to their seats from intermission when Matthew Tkachuk sailed a long shot in past Juuse Saros 15 seconds into the period. Saros then gave up another softie to Jake Guentzel, and Brady Tkachuk beat the struggling Nashville Predators goaltender again to make it three U.S. goals in less than three minutes.

That onslaught quieted the very pro-Finland crowd full of Canadians eager to root against their country’s biggest hockey rival. Some even booed the U.S. anthem before the game, and there was plenty more where that came from for Toronto Maple Leafs captain Auston Matthews several times he touched the puck.

Matthew Tkachuk added another for good measure on the power play with 8:47 left, and that was enough for the “U-S-A! U-S-A!” chants to fill the bowl at Bell Centre. In the waning minutes, a few U.S. fans proclaimed, “We want Canada!”

Finland only gave fans one real opportunity to cheer, when late-added defenseman Henri Jokiharju beat Connor Hellebuyck clean on a shot 7:31 in to make it 1-0. Hellebuyck stopped the next 18 shots he faced to finish with 20 saves.

The same could not be said for Saros, who allowed six goals on 32 shots and could be replaced in net by Kevin Lankinen for Finland’s game against Sweden on Saturday.

Family ties

Charlie McAvoy and Mike Sullivan have a strong connection off the ice that goes way beyond hockey.

McAvoy is married to Sullivan’s daughter Kiley, who recently gave birth to the couple’s first child. McAvoy plays defense for the Boston Bruins, Sullivan coaches the Pittsburgh Penguins and their careers had not overlapped until now, when they’re on the same team with the United States.

“I have a son now, for his dad to play for his grandpa, those are things that I would have never dreamed of,” McAvoy said. “This is just where hockey’s taken us, where our jobs have taken us, so it’s extremely special.”

Sullivan, the U.S. team’s head coach, called it an incredible privilege and thinks he and McAvoy will gain a greater appreciation of this looking back on it.

“Someday we might look back on this and smile,” Sullivan said. “Charlie means the world to us, to our family. First and foremost, he’s a terrific hockey player. He’s fierce competitor. But more importantly than that is he’s a great kid and a good person and he means the world to our family.”

Rhys Michael McAvoy was born in late January. Sullivan joked he had “zero input” on the name Kiley and Charlie chose.

But adding to their family just before being together for an international tournament only added to their joy.

“What it’s like when him and my daughter just had their first baby, for my wife and I, it’s an incredible thrill,” Sullivan said. “It’s certainly a privilege to be a grandparent, and we’re enjoying that process also. And it’s new. He’s only 2 weeks old, I believe. It’s exciting times for our family. This event just adds to the excitement. I’m certainly, from my standpoint, I can’t tell you what it means to me to have the opportunity to share in this event with him.”

McAvoy said he does get teased a bit by his U.S. teammates, but he added that he and Sullivan are professionals and there’s no concerns about the dynamics of playing for his father-in-law.

“Everybody gets it at this point,” McAvoy said.