MELBOURNE, Australia — A United States women’s national soccer team entering unfamiliar straits will encounter a familiar adversary Sunday in the World Cup round of 16. Given the tumult of the group stage — and of coming within a whisker of being eliminated at an unfathomable early point — perhaps colliding with a frenemy is just what the Americans need to climb out of their funk.

“It wouldn’t be a major tournament if we weren’t facing Sweden,” midfielder Lindsey Horan said with a grin.

“We know them very well,” forward Alex Morgan added.

The U.S. women’s national team faces Sweden in the round of 16 at the World Cup on Sunday at 5 a.m. Jabin Botsford/The Washington Post

The teams will tangle for the sixth consecutive World Cup and the eighth straight time in official competition, including the Olympics.

Never before, though, have the World Cup stakes been so high. All other meetings have come in group play, with the United States winning three, tying one and losing one in the most recent contests. The Swedes have prevailed in the recent Olympic matches — a 2016 quarterfinal shootout and in the group stage at the Tokyo Games.

This year, the teams figured to sidestep each other until late in the tournament, even though they were in groups paired for round-of-16 matches. Both were favored to finish atop their respective quartets. Only Sweden met expectations, racing through Group G with three victories and one goal conceded. In Group E, the United States finished second to the Netherlands, which will face South Africa.

Consequently, the Americans and Swedes will meet for the 43rd time — the U.S. team’s fourth-most-common opponent behind Canada, China and Norway.

Sweden is in terrific form; the United States is not. Sweden rested most of its starters in the group finale against Argentina; the United States has squeezed a lot of minutes out of the regulars and will play without attacking midfielder Rose Lavelle (yellow-card suspension).

Sweden has fresh memories from the 2021 meeting at the pandemic-delayed Summer Games in Tokyo, one of the darkest days for the U.S. program at a major tournament.

“If you’re going to go all the way, you’re going to have to play this kind of opposition sooner or later,” Swedish Coach Peter Gerhardsson said. “From a psychological perspective, we know we can beat them.”

Sweden is one of the few teams to give the United States fits on any stage and in any decade. The past nine meetings have left the Americans with three victories, two defeats and four draws, including one the Swedes won in a shootout.

“It’s always a massive battle — physically, mentally, everything that goes into it,” Horan said. “So it’s going to be a constant focus on everything.”

CHANGES AHEAD?: A primary focus will be on offsetting corner kicks. Four of Sweden’s nine goals have come off those deliveries. Left-footed Jonna Andersson delivers in-swingers from the right side, and right-footed Kosovare Asllani does likewise from the left. Their targets are tall, strong and efficient.

Meanwhile, the Americans will need to show marked improvement in their passing, chemistry, speed of play, speed of thought and scoring execution. Except for moments throughout the opener against Vietnam and most of the second half against the Netherlands, the United States has been a dud in this tournament. The five points earned in group play were the fewest in its World Cup history.

“It’s not a good feeling to have, and that’s why we’ve looked at ourselves and looked at these last few games,” Horan said. “We know that part is over, and now we have to go find (improvement) inside of ourselves.”

The players have accentuated positives: They have yet to lose a game, and they allowed one goal. Overall, though, it has not been good enough.

“It’s no secret that we feel like we can play better,” forward Lynn Williams said. “The name of the game the whole time is to get out of the group stage. And that’s exactly what we did. Tournaments are about results, and we’re getting the results.”

The results, though, have fallen far short of expectations for a two-time defending champion — and four-time overall champion — that hasn’t lost a World Cup match (aside from a shootout) since 2011 and is 41-4-8 in World Cup history.

Because things aren’t working well, U.S. coach Vlatko Andonovski might need to adjust his lineup and tactical plans. If changes are in the works, he will not reveal them until 90 minutes before kickoff.

Would he consider moving Julie Ertz from the back line to defensive midfield to add a physical presence? Would Crystal Dunn be more effective in midfield — her NWSL position — than at left back? Is it time to try center back Alana Cook and midfielder Ashley Sanchez?

Regardless who is on the field, a U.S.-Sweden women’s match is a throwback. Since the inaugural World Cup in 1991, they have been among the most consistent and successful programs. (Sweden is a four-time World Cup semifinalist and two-time Olympic silver medalist.)

SHOWCASE GROWTH: While Sweden is still seeking a breakthrough and the U.S. performance has slipped this year, the quality of competition has grown substantially.

This year, second-ranked Germany, reigning Olympic champion Canada, 2019 quarterfinalist Italy and perennial power Brazil failed to qualify for the knockout stage. Their places were taken by Morocco, Nigeria, South Africa and Jamaica. Colombia has also been a surprise.

“We said before this tournament this would be the most competitive World Cup, and if you’re not watching it, you’re really missing out,” Horan said. “It is showing the investment in women’s sports and women’s football. Every result you see, it’s insane. Some of the games that we’ve played, it’s not easy; it’s difficult and it’s a World Cup. It’s getting better and better and better.”

UNITED STATES VS. SWEDEN INFO

Game time: Sunday, 5 a.m. EST.

How to watch USWNT-Sweden: Fox, Telemundo, Universo and Peacock (streaming).

USWNT women’s World Cup group-stage recap: The U.S. women opened group-stage play with a 3-0 win over Vietnam, then played to a 1-1 draw against the Netherlands. Their final group game was a scoreless draw vs. Portugal that triggered alarm bells in Oceania and the United States.

USWNT-Sweden at the Tokyo Olympics: Sweden stunned the U.S. at the Tokyo Games in 2021, dominating the Americans and rolling to a 3-0 win in group-stage play. In the aftermath, The Post’s Adam Kilgore wrote: “In U.S. Coach Vlatko Andonovski’s major tournament debut, Sweden left no doubt about which team deserved to win. The Swedes were faster, stronger and better.”