MEXICO CITY — There is a tendency among professional athletes and coaches, when faced with the hype of high-stakes competition, to undersell the sense of occasion.

A big game, they might say, is in fact just another game. Looking ahead at a stretch of daunting contests is futile; better to go one day at a time.

But when the United States men’s soccer team gathered this week in preparation for its final three qualification games for the 2022 World Cup, Coach Gregg Berhalter was uncharacteristically blunt with his staff.

“This is probably the biggest week of our lives as professional coaches,” Berhalter said he told them. “That’s just honest.”

On Thursday in Mexico City, Berhalter and his team embarked on a set of matches — three of them, in three countries — that will determine if they will return to the World Cup for the first time since 2014. It is unlikely the fate of either the United States or Mexico will be decided on Thursday night; results in other games could change the math, injuries and absences have complicated both teams’ plans, and two more matches remain after Thursday, offering either confirmation or a last-ditch lifeline.

A place in the world’s biggest sporting event is typically motivation enough. But Berhalter and his players have been burdened with the task of redeeming the failures of their predecessors, of smudging away the memories of 2017, when the team squandered a ticket to the 2018 World Cup in stunning fashion.

The current group, the great majority of whom played no role in the failure of five years ago, began the day in second place in their regional qualifying group — a strong position, given that the top three teams earn an automatic spot in the tournament and the fourth-place team gets a chance to make it through a play-in game. But the disaster of Couva, Trinidad, in 2017 means the United States long ago surrendered the privilege of tranquil optimism.

After their game against Mexico on Thursday, the Americans will play Panama in Orlando, Fla., on Sunday before traveling to Costa Rica for their final qualifier on Wednesday night.

“We just have to qualify — there’s just no other option,” midfielder Tyler Adams said. “I think that when you’re in big games, important games, you always have to remember what motivates you and what you’re doing it for. And for us, we’re doing it for all the U.S. fans. We don’t want to let down our nation.”

All week the American players have repeated the word “responsibility,” the understanding that their fortunes in these games will ripple far outside their group, and well into the future.

That remains one of the curious aspects of national soccer teams: their reputations, their standards, their expectations, how people perceive them to play, how people evaluate their characters — these things get passed through generations, even as players and coaches and other personnel change.

The same could be said for their traumas. In 2017, the Americans went to Trinidad knowing that a win or a draw would guarantee them a ticket to the World Cup. Instead they lost, and a series of unlikely results in simultaneous matches on the final day left them on the outside looking in for the first time in a generation. The American players finished the night slumped on the field, some of them with tears in their eyes. A few, like the star Christian Pulisic, did not speak publicly about their disappointment for months.

Time moves slowly in international soccer. The images and sensations of that night — the heartbreak and disgust and nausea — continue to stalk the program. Adams talked this week about watching that match on his couch at home. He said he spent the ensuing years wondering if he might have sneaked onto the World Cup roster if the team had qualified for Russia.

“Hopefully we have all learned from the past that we need to be better,” said midfielder Paul Arriola, one of the few current players who was part of the last qualifying campaign.

As the last stage of that effort began Thursday at the Estadio Azteca in Mexico City, the United States and Mexico found themselves in the unusual, uncomfortable position of looking above in the standings and seeing someone else — Canada — in the top spot they have long claimed as their own.

Mexico is ranked 12th in the world by FIFA. The United States is 13th. Canada is 33rd. But Canada — which was unbeaten against the U.S. and Mexico in qualifying (2-0-2) — has looked to be the most assured, the most dangerous team in the region over these past months, while the two traditional powers have struggled more openly with the highs and lows of the grueling, monthslong competition.

The Americans started the process last September with youthful bravado. Never mind that the majority of them had never experienced the stress and strain of World Cup qualifying matches in this region. Midfielder Weston McKennie declared the team would look to “dominate” the tournament. Adams trumpeted their lofty target: “Nine-point week, bottom line,” he said heading in to the team’s first three-game window.

Those things did not happen. The team’s first two games were duds, and they finished the first window with five points instead of nine — no reason to panic, but a cold reminder of the challenge that lay ahead. Since then, it has been a learn-on-the-fly process of melding the team’s many raw talents into a coherent group.

Berhalter, who has openly marveled at the difficulty of managing such a young team in such a tough circumstance, has gone through a learning process of his own.

“When you’re at a club, it’s a building type of thing,” said Berhalter, who coached for almost a decade at the club level before being hired by U.S. Soccer in 2018. “When you’re at a national team, I think it’s a winning type of thing. My mind-set had to change to be much more about winning every game. That’s what we want. That’s obviously what the public wants. Winning also means qualifying.”

The urgency of that task was felt most acutely by the people who were on the field four years ago. Pulisic, for instance, was one of the players with tears on his face after the loss in Trinidad.

“I’ve been looking forward to it for years now,” he said about washing away the bad taste of that experience. “Of course we use it as motivation. We were extremely upset. And now we want to qualify. We have the opportunity now. We definitely don’t want to go through that again.”