Tony Popovic's side was the authors of its own downfall, going behind to an own goal in the 11th minute and Alex Freeman added a second for the American side just before the break.

Although the Socceroos improved in the second half, they never threatened to mount a serious challenge to Mauricio Pochettino's men, but Popovic wasn't surprised in what he saw from the tournament co-host.

"Their quality is clear, their power is clear, their athleticism is clear," he said after the match.

"There are no surprises in what they did. We didn't match that in the first half. We found it difficult to win a challenge, to win a second ball.

"We were slow to every ball, and we couldn't really wrestle back any momentum, which made it difficult – and look, we conceded a couple of soft goals really for us. They were soft goals, but we just looked flat and lethargic in the first half."

The 52-year-old made three changes at the break and praised his young side for improving.

"We don't have the experience of playing in big leagues and having the minutes under our belt, but the response, where you can easily cave in under the pressure, physically, emotionally, we responded extremely well," he said.

"I'm really pleased with the second half, and it would have been nice to get a goal in those moments that we had, to just see what could happen next. But everyone should be very happy with how they responded after the break."

Popovic paid tribute to the USA, which picked up a second win of the tournament to advance to the knockout stages with a game still play against Turkiye, which is desperate for a win after losing to Australia last week.

"We needed to stay in the game better than what we did in the first half, but you've got to give them credit as well.There's a reason why they are so good," Popovic said.

The Socceroos are still in the hunt to make the Round of 32 with the USA, and faces Paraguay in its final group game on 26 June (AEST).

Australia defender Harry Souttar is already looking ahead to that match.

"We've shown in the friendlies before [the tournament] and in the game against Turkey [Turkiye], we're a resilient team, and that's all about recovery now and full focus on Paraguay," he said.

United States managed to win with relative ease despite missing star man Christian Pulisic, who was held back after sustaining a calf injury in the opening win over Paraguay.

"It's always difficult because we want to have all the players," Pochettino said.

"Christian is an important player for us. But it was impossible today for him to play. We hope that next game he will be available."

Pochettino said Pulisic remained central to his plans but added that any successful 2026 FIFA World Cup run would require contributions from the entire squad.

"If we want to win the competition, we need the whole team," he said. "All the players need to be important.

"Of course, Christian is one of the best players in the world. I hope that he can recover as soon as possible and can enjoy being on the pitch and helping the team."

Weston McKennie praised the USA's depth and said the squad showed that it could do it all against Australia.

"We can play the physical game because we have guys on the field who are ready to step up for that, " he said.

"And we have guys with quality who can play possession-based football."

United States will close out its Group D fixtures against Turkiye next Friday (AEST) at Los Angeles Stadium.