- Brandon Vázquez (29')
- Luka Ilic (43')
- Veljko Simic (46')
Dual nationals Brandon Vazquez and Alejandro Zendejas got the start as interim coach Anthony Hudson handed eight players their senior team debuts -- seven as starters -- with Vazquez opening the scoring in his first appearance for the U.S. on a silky, glancing header from Julian Gressel's cross into the area.
Chelsea goalkeeper Gabriel Slonina, who was also making his debut for the senior U.S. team, made several key saves over the course of the first half but was beaten at his near post by a Luka Ilic free kick to level the score for Serbia ahead of half-time.
Serbia then took the lead right as the second half began when Veljko Simic capitalized on some poor defending by the U.S., pounced on a loose ball just outside the area and beat Slonina from close range to make it 2-1.
Cade Cowell, who was lively all night on the left for the U.S., twice hit the post in the following minutes and blazed a swerving shot wide of the Serbian goal soon after.
"I have to say overall, I was really pleased with the performance," Hudson said. "I loved the fact that players were really driving to get forward and run behind the line and attack the back line. So I'm disappointed, obviously, with the result, but the way they went about the game was pleasing to me."
The American team is in transition with interim head coach Hudson running the show while the U.S. Soccer Federation determines the future of coach Gregg Berhalter, whose contract expired at the end of last year.
Hudson is using the team's annual January camp and the accompanying exhibitions to give experience to a new crop of prospects after the U.S. was eliminated in the round of 16 at the World Cup in Qatar.
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The U.S. uses youngsters and MLS players in its winter camp, which falls outside a FIFA international window. The current group has 11 players getting their first call-up and just five members of the World Cup roster.
Hudson's inexperienced group put on an exciting performance with much more action and attacking flair than normal in these annual January exhibitions, but the U.S. team has won just one of its past eight matches, with four draws and three losses.
"I told the guys before the game in the huddle that anytime you put on this jersey, whether it's in January or in a World Cup game,' you have to have pride," said U.S. captain Walker Zimmerman, whose 38 international appearances were 10 more than the other 21 starters combined.
"You never want to lose a game, but sometimes it's good to get experience for guys and welcome them into this brotherhood. That's what we feel great about."
Goalscorer Vazquez added: "Making my debut tonight and scoring on my debut with my family here close to where I grew up, it's something incredible. Seeing my family celebrate like that and it's, it's something amazing to see."
Next up for the U.S. is a friendly against Colombia at Dignity Health Sports Park in Carson, California, on Jan. 28.
Information from Associated Press and Kyle Bonagura was included in this report.
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