KASHIMA, Japan — The referee’s whistle had barely finished chirping when the Canadian players sprinted to the middle of the field and unleashed an explosion of exaltation that echoed around an otherwise silent stadium.

They formed a tight ring, bouncing, laughing, yelling. Minutes passed. The cheers went on and on. The players had a lot to celebrate, years of pent-up emotion to release.

On a steamy Monday night at Ibaraki Kashima Stadium, Canada notched an unexpected, but not altogether unlikely, 1-0 victory over the United States in the Olympic women’s soccer tournament, scoring a late second-half penalty kick to secure a place in the gold medal match on Friday night in Tokyo.

It was a breakthrough of sorts for the Canadians, who won bronze medals at the previous two Summer Olympics, in 2012 and 2016, but have a bitter history against the United States. On the other hand, it felt like a culmination of an era for the United States, whose players struggled afterward to put their finger on what exactly had gone wrong throughout the tournament.

“Job One is done for us: changing the color of the medal,” said Christine Sinclair, 38, the captain of Canada, who will face Sweden or Australia in her first final of a major tournament after appearing in five World Cups and three previous Olympic Games. “Now that we’re in the final, we go for it.”

After the final whistle, as the tornado of Canadian jubilation continued to swirl, Carli Lloyd of the United States was crouched on the grass, completely still, pulling her head down in her hands.

The United States, the No. 1-ranked team in the world, had been hoping to follow up their 2019 World Cup title with an Olympic gold medal. But they never could put the necessary pieces together in Japan, never looked quite like the juggernaut they have been for generations.

“I was just gutted,” said Lloyd, 39, a two-time gold medalist and the oldest player on the team. “We wake up early. We train late. We sacrifice. We give up so much, and you want to win. Sometimes you win, and sometimes you don’t. It’s just heartbreaking, really.”

With that, a golden chapter of American soccer appeared to come to an end. The program may continue its run of success at major tournaments to come, but it will not be with this group of players, many of whom have become household names.

After the game, in the tunnel leading off the field, Megan Rapinoe, 36, was asked what the future held for the group. Her voice seemed to waver as she pondered the question.

“Obviously there’s a few of us that are closer to the end than the beginning, and we’ve had an amazing run, a lot of nights that looked different than that,” she said. “We’ve been through so much together.”

“We’ve done our job,” she added about her generation of players. “But you never want to see it end.”

The game had an inauspicious beginning for the Americans. They lost their star goalkeeper Alyssa Naeher, the penalty-kick shootout hero of their quarterfinal victory over the Netherlands, to a right knee injury just half an hour into the match.

But in the end, it was a shot that no goalkeeper would have saved that sank them.

In the 74th minute, Canada midfielder Jessie Fleming strode to the penalty spot after a video review of a foul awarded her team a chance to take the lead. Taking a breath and clearing her head, Fleming lashed her penalty kick high and hard to the left of Adrianna Franch, the backup goalkeeper who had sprinted on to replace Naeher in the first half. When the ball rippled the side netting in the corner of the goal, it sent her team into raucous celebrations.

A penalty call had not been made initially on the field, but it was confirmed by a second look from the video assistant and the match referee, Kateryna Monzul of Ukraine. On the play in question, United States defender Tierna Davidson and Canada forward Deanne Rose came together as they chased a bouncing ball in the penalty area. Davidson took a swing at it, but missed, and instead clipped the leg of Rose, who went tumbling to the ground.

Monzul reviewed the contact on a sideline monitor and then returned and, dramatically, pointed to the spot.

“Jessie was cool, calm and collected,” Rose said. “We work so hard, we don’t give up, and we’re going for gold.”

The loss sent the Americans spiraling out of a tournament in which they never looked totally comfortable. They fell to Sweden, 3-0, in their opening match and seemed tentative and ponderous at various points thereafter.

The result in this tournament is likely to be deemed a failure for Coach Vlatko Andonovski, who was hired in October 2019 and tasked with maintaining the lofty status of the best team in the world. For nearly two years he had done that; the Sweden loss to open the Games was the first of his tenure, but its effects lingered as the team tried to move on.

The players struggled to pinpoint exactly what went wrong in Japan. But both Lloyd and Rapinoe, who started Monday’s game on the bench, suggested they struggled with Andonovski’s “rotations” — that is, the way the coaching staff managed their personnel — and other players, notably striker Alex Morgan, did little to disguise their disagreement with the coach’s tactics at times.

“I feel like we haven’t had our joy a little bit, hasn’t flowed for us, hasn’t been easy,” Rapinoe said. “We have tried to find it. It is not for a lack of effort. It didn’t click for us. I don’t know if it was roster rotations.”

As the Canadian players celebrated their victory, the Americans lingered on the field, trying and failing to find the words to alleviate the pain of the moment for one another.

“No one knows what to say, and everyone just wishes they could turn into dust,” Rapinoe said. “But that’s not how it works. We have another game. We still have another medal to compete for. It’s obviously not the type of medal we wanted.”

Long after her teammates had departed the field, Lloyd walked over to the end line and began sprinting. To the first line and back. Then the second line and back. And then next.

“If we’re not going to walk away with a gold medal, I’d like to walk away with a bronze medal at the very least,” Lloyd said.