Max Domi scored twice, including one of two empty-net goals, as Canada hung on for a 5-3 victory over the United States on Wednesday.
The win put Canada (4-0-0) into what should be an easy quarter-final against Denmark in Toronto on Friday, while the Americans (2-1-1) will stay in Montreal for a tough quarter-final against Russia.
"I thought we had good flow throughout the game," said Canadian captain Curtis Lazar. "You have to give the Americans credit. They didn't go away, or roll over and die.
"They made it quite interesting. I was freaking out a bit at the end, but we found a way to win."
Canada wore down the Americans with high-tempo hockey from its top three lines and a strong checking game from the fourth unit. They had a 43-28 shot advantage, including a long stretch of the second period when it was one-way hockey.
But the U.S. didn't go down without a fight, as Dylan Larkin scored twice in the third frame to draw his team within a goal, only to see Canada put it away with empty-netters by Domi and Sam Reinhart.
"If they don't score those two empty netters, we scored the same amount of goals as Canada," said U.S. goalie Thatcher Demko. "We were right there, toe to toe with them.
"It could have gone either way. Credit to Canada, but it was nice to see us battle and compete at the end."
Josh Morrissey scored as Canada's red hot power play went 1 for 2 to maintain a .500 success rate over four games. The penalty killers conceded a goal for the first time in 15 tries to U.S. rearguard Anthony DeAngelo, however.
Lazar also scored, while Reinhart had a goal and two assists to take the team lead with eight points.
The largest, noisiest crowd so far at the Bell Centre — 18,295 in attendance — saw a fast-paced and physical game in which the Finnish and Swedish referees mostly kept their whistles in their pockets.
The pre-game hype was all about Canada's Connor McDavid and the Americans' Jack Eichel, slated to go one-two in the NHL draft. While both played well, neither dominated but each had an assist.
"It was exciting," McDavid said. "The U.S. has a great team. It was a lot of fun."
Eichel and the top line with Alex Tuch and Tyler Motte found themselves all game against Canada's shutdown pairing of Shea Theodore and Darnell Nurse, who left them little room to play their cycling game.
"Me and Nursy knew we'd be matched up against him and I thought we did a really good job," said Theodore. "He's fast, he's got great hockey sense. He knows what areas to go to get opportunities."
"You can take a lot out of a loss," said Eichel. "That's what we'll do and we'll be better for it."
The Canadian goaltending question remains unanswered.
Eric Comrie, taking over from Zach Fucale, was solid as the Americans created some dangerous chances early that made it appear he had sewn up the starting job. But then he gave up two third-period goals.
Fucale and Comrie each started two group stage games. Coach Benoit Groulx said he has yet to decide who will be in goal now that single-game knockout play is about to begin.
"We have no set plan," Groulx said of his goaltending.
Groulx liked his team's play, but while Canada once again dominated the faceoff circle, he said the Americans "did a better job than we did of jumping on the puck and going to the net."
It is an area they hope to fix, he said.
Canada led 3-2 late in the third when Reinhart scored into an empty net. Larkins got his second of the game with 42 seconds left to play, but Domi put it away with another empty-netter with five seconds to play.
A quick pace was set early as the teams exchanged scoring chances at both ends in a first period in which Canada outshot the Americans 17-13. And the nastiness began even before the opening faceoff as Anthony Duclair and Motte did some shoving.
But Canada took over in the second period, although it took until their 24th shot to beat Thatcher Demko. They did it with speed as Domi fired a puck on a rush and then banged in a pass off the rebound from Sam Reinhart at 7:07.
Canada's power play struck at 10:11 as Morrissey drilled a shot inside the near post from the right circle after passes from Robby Fabbri and Nic Petan.
The Canadians conceded a power-play goal at 12:23 as a pass got through a maze of sticks in front for DeAngelo to fire into an open side.
McDavid blasted down the left wing and saw the rebound of his shot go in off Lazar, who skated hard into the crease, at 10:01 of the third period. The goal stood up to video review.
"I knew it was a good goal," Lazar said. "What a play by Connor. I just drove the net. They aren't going to be pretty all the time. It was the right call upstairs."
It was the largest crowd to date at the Bell Centre and the they were singing and chanting until an errant pass from Dillon Heatherington to Joe Hicketts in Canada's zone was turned into a tic-tac-toe goal finished at the side of the net with Larkin's first goal of the game.
Of note was a strong game by Canada's fourth line of Frederik Gauthier, Lawson Crouse and Nick Ritchie, who consistently kept the Americans in their zone.
Notes — It was the 10th time Canada and the U.S. have faced each other on a New Year's Eve. Canada holds a 7-3 edge in those game, winning the last six. . . Canada moved Jake Virtanen onto the McDavid line, dropping Ritchie to the fourth unit.