It is one of the greatest rivalries in sports, and when Canada defeated the U.S. 4-2 to lock up first place in Group A, it was the most exciting hockey we've seen yet at these 2022 Olympics.

In Tuesday's battle between the North American superpowers at the Wukesong Sports Centre, Canada was outplayed for stretches in both the first and third periods. But the 2021 World Champions stayed the course, got world-class goaltending from starter Ann-Renee Desbiens (51 saves) and capitalized on their chances to stay perfect with a fourth straight win. The Canadians got three goals in 7:25 in the second period.

In total, the U.S. outshot Canada 53-27.

"We just wanted to be relentless all over the ice and I think we had a couple of moments where we got a little bit sloppy and not as aggressive as we normally are, and that’s where we give the other team life," said Canada's Sarah Nurse. "I think once we got back to those principles that we want to instill, we had a pretty good game."

Brianne Jenner stepped up with a pair for Canada and now shares the Olympic goals lead with teammate Sarah Fillier (five). Captain Marie-Philip Poulin cashed in on a penalty shot for her first goal of these Games and added an assist, and Jamie Lee Rattray got her third goal of the tournament.

Dani Cameranesi and Alex Carpenter replied for the defending Olympic champion Americans, who lost their first game in Beijing.

Asked what the U.S. needs to do to improve in the medal round, Olympic rookie Abbey Murphy said: "Not letting down in the second period. I think we had some tough shifts and you can’t do that, especially against Canada."

High-octane offence was expected and provided. Canada now has 33 goals in four games – more than the Finns, ROC team, and Swiss combined. Coach Joel Johnson's American women are up to 20 goals.

The Canadians, winners of four Olympic gold medals (2002, 2006, 2010, 2014), are hungry to regain the title they dramatically lost to the Americans, 3-2 in a shootout, in Korea in 2018. Likely, a rematch with the Americans looms on 17 February. The cross-border rivals have squared off in every Olympic final except 2006, when Canada beat the Cinderella Swedes 4-1.

Canadian coach Troy Ryan gave Desbiens her third start after Emerance Maschmeyer earned the W in Monday’s 6-1 win over the ROC team. Desbiens was as technically brilliant as her battle level was high.

"She was stellar today," said Nurse. "I’ve been on the same team as her the last six, seven, eight years and I think that was one of the best games I’ve ever seen her play. She was just calm, collected and poised. She really made it look easy."

U.S. goalie Maddie Rooney got her second Beijing start after stopping 10 of 12 shots in the opening 5-2 win over Finland. Rooney is best-known for starring in the 2018 Olympic gold medal game, foiling 2010 MVP Meghan Agosta on Canada’s final shootout attempt.

"Overall, I thought we played a great game as a team," Rooney said. "We got a lot of shots from the perimeter, but we’ve just got to get better chances in tight around the net and capitalize. We’ll learn from this game and I feel good about our offensive game moving forward."

Psychologically, this was a big game for Canada to get the top playoff seed. Still, it's worth remembering that Canada edged the U.S. 2-1 in the group stage in 2018 and yet settled for silver. No room for complacency.

The Americans picked up steam early and dominated the first period with their aggressive forecheck, earning a 16-5 edge in shots. They hemmed Canada in its own end – something not previously seen in Beijing – midway through the first.

Power forward Abby Roque created a turnover, busting down the middle, and backhanded the puck off Desbiens’ right post. Moments later, a blast by Murphy ricocheted off both posts. The Canadian goalie had to stand on her head to keep the game scoreless.

Natalie Spooner, who leads the Olympics with 11 points, said of the Americans: "They are a lot faster (than other teams) and you’ve gotta get used to making your decisions quicker. Maybe it takes a shift or two to feel your legs and get them moving."

Entering this game with the tournament’s top power play (41.6 percent), Canada shifted the momentum by opening the scoring on a 5-on-4 at 14:10. With U.S. Olympic rookie Caroline Harvey off for cross-checking Sarah Fillier from behind, Poulin fed the puck from the left faceoff circle to Fillier at the goal line, and her one-touch centering pass found Jenner, who surprised Rooney with a high shot.

In the second period, blood was shed, but not because both teams drove to the net fearlessly. U.S. veteran Amanda Kessel inadvertently clipped referee Cianna Lieffers with a high stick and cut her. She went off for repairs and the play continued with three on-ice officials until Lieffers returned with a Band-Aid.

On a 4-on-2 rush, Alex Carpenter, who scored both U.S. goals in the 2021 Women's Worlds final, shot high and wide on the U.S.'s best chance on its second power play. But the Stars and Stripes were coming on.

Desbiens couldn't do it all by herself. Cameranesi jumped up to get a Kelly Pannek feed from behind the goal line, grabbed the rebound from Canada's first save, and slid it into the gaping cage at 9:17.

An exciting rush led by Roque led to America's second goal. Roque found Kessel in the middle and she skimmed it to partner-in-crime Carpenter, who let Desbiens go down before roofing a backhander for a 2-1 lead at 11:34.

Jenner got the equalizer for Canada just 26 seconds later. Going hard to the net, she one-timed Nurse's pass from the right side past Rooney's right skate. Jenner now has 12 points in her last 11 Olympic and Women's Worlds games against the Americans, more than any skater on either side.

Rattray made it 3-2 Canada at 14:25. Spooner tried a backhand wraparound and the puck squirted right out to Rattray, who made no mistake.

"It seemed like every time we stubbed our own toe, it ended up in the back of our net," said Johnson.

With under three minutes to pay in the middle frame, Cayla Barnes hooked Poulin on a shorthanded breakaway and the captain was awarded a penalty shot, the first one in Canadian Olympic women's hockey history. She curled in from the left side and got the puck past Rooney's blocker for a 4-2 lead.

"It felt great, obviously," said Spooner. "I think Marie-Philip would have buried the original shot if she’d got in there. She’s a goal-scorer and can score those big goals, and I think it gave the whole team a lift."

In the third period, the Americans refused to cave, outshooting Canada 21-6. But Johnson pointed out: "It’s great to get zone time and shots on goal but when they’re blocking as many as they did, shots don’t matter. We’ve got to find a way to generate higher-quality chances if we expect to win a game like this."

The U.S. had a great chance to narrow the gap when four-time Canadian Olympian Rebecca Johnston was penalized for unsportsmanlike conduct after shoving Hannah Brandt. But the Canadians killed it off with authority.

"There's a lot of pride on the line and a lot of hostility out there," Nurse said.

Johnson pulled Rooney for the extra attacker with 2:37 left when Blayre Turnbull got dinged for tripping. But the 6-on-4 was fruitless. Unlike many other U.S.-Canada games, there would be no wild comebacks.

"We’ve got more big games coming up, so you’ve gotta have a short-term memory," Rooney said. "We have to learn from the mistakes, but not get too down about it and just move on to the next one."

Of facing more than 50 shots, Desbiens said: "It actually didn’t feel too bad. I guess in the first period, yes it did! We had a lot of defensive zone time, but in the second and third [periods] we were able to get it out more often."

The Canadians have been red-hot lately. After defeating the U.S. 3-2 in overtime on Poulin’s goal to win the 2021 Women’s Worlds, they carried that momentum into the pre-Olympic Rivalry Series. Fillier starred with a series-high five goals and Poulin scored sudden-death winners twice as Canada won four out of the six Rivalry Series games.

This was the ninth all-time meeting between Canada and the U.S. at the Olympics. Canada’s record now sits at six wins and three losses.