United States midfielder Julian Green controls the ball as Brazil...

United States midfielder Julian Green controls the ball as Brazil forward Douglas Acosta defends during the first half of an international soccer friendly match. Credit: AP/Julio Cortez

Essentially, it was men against boys.

The final score might have read Brazil 2, U.S. 0, but the disparity between the two teams was far greater than the scoreboard indicated in the international friendly at MetLife Stadium Friday night.

There were some tough lessons learned, but if the U.S. wants to avoid missing its second consecutive World Cup, these young players need the experience against the world’s best teams in what kicked off a six-game Fall Kickoff series.

“It’s a baptism by fire in a lot of ways,” said U.S. captain and midfielder Wil Trapp, who made his fourth international appearance. “We’re earning stripes, man. This is a game where lessons are learned, and they’re learned harshly because a team like this can punish you and they did. Understanding that we’re only going to get better and we’re going to improve playing difficult opponents is a big step for us.”

Interim head coach Dave Sarachan deployed a starting 11 that averaged 22.5 years. Ages ranged from the Red Bulls’ 19-year-old midfielder Tyler Adams to three 25-year-olds —  defender John Brooks, forward Bobby Wood and  Trapp.

Though the visitors brought a B team, they showcased superior skills, experience and soccer IQ before a pro-Brazilian crowd of 32,489.

Firmino volleyed home Douglas Costa’s right-wing cross from close range past goalkeeper Zack Steffen in the 11th minute. A questionable penalty-kick call led to a 44th-minute goal after Trapp appeared to have knocked down Fabinho in the area. Neymar converted the penalty.

“It was pretty evident that we had a nervous start,” Sarachan said. “The ability to connect passes was difficult for our group early in the game. When you concede possession against a team like Brazil, it makes it hard. You do a lot of chasing.”

Tim Weah, the son of legendary Liberian forward George Weah and who grew up in Rosedale, Queens, received a nice ovation when he replaced Kellyn Acosta in the 56th minute.

Christian Pulisic, the best of the young Americans, is sidelined with a muscle injury. “If we had Christian tonight, I can’t say we’d have the ball more than 40 more percent of the time,” Sarachan said. “Clearly when you add players into the mix that have a certain comfort level and can play out of tight spots like Christian it would help. Sure, we miss Christian. I’m not sure it would have changed the way the game went.”

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