It was the ninth win in a row for four-time world champion Germany, which is looking to restore its dented international reputation after first-round exits at the 2018 and the 2022 FIFA World Cups.

Germany, which suffered a blow when teenage star Lennart Karl was ruled out of the tournament with a muscle injury in training on Saturday (AEST), took the co-host by surprise with a strong start.

Kai Havertz found far too much space in the box and headed in Joshua Kimmich's free-kick to give it a second-minute lead.

USA gradually recovered as the visitors took their foot off the gas, and snatched a stunning equaliser when Antonee Robinson thundered in a volley in the 37th minute after defender Jonathan Tah had headed a corner away.

The tables were turned after the break with Germany taking control and Sane, who came into the starting line-up for the injured Karl, rifled in from the edge of the box to put Germany back into the lead in the 57th.

The game lost some pace in the second half with both teams making a number of substitutions, and Gemany saw it out for the win.

Despite the defeat, USA boss Mauricio Pochettino was thrilled with the competitiveness that his side showed.

"Overall, I think it ​was a good performance. I am happy with the performance of everyone. We play one of the most important teams in the ​world," Pochettino said.

"I think we need to be ​happy with that. We compete, [we were] unlucky, I think it was an even game... It was an amazing challenge for us to see how we react, how we show character, how we show togetherness, how we start to play under pressure.

"We were demanding ​a lot to the players in the ​last two ⁠weeks. I've seen [us] overload the players and the team.

"Now [we have] to assess the load and be ⁠intelligent ​in the way that we are ​going to arrive to the Paraguay [game], in the best condition, fresh with ​energy."

United States will also face Australia and Turkiye in Group D as it looks to advance to the knockout stages for the fourth consecutive FIFA World Cup.