Christian Pulisic has a strained right quadriceps and returned to Germany for treatment, the U.S. Soccer Federation said on Wednesday.
The 20-year-old midfielder scored in the fourth minute of Tuesday night's 1-1 exhibition tie against Chile, then left late in the first half because of the injury.
The USSF said Pulisic had an MRI after the game and was returning to club side Borussia Dortmund, who will establish a timetable for his return.
Pulisic has been limited to 15 league matches and 25 overall this season for Borussia Dortmund. He tore a calf muscle last October and a thigh muscle in February, and lost playing time because of the emergence of 19-year-old English winger Jadon Sancho.
He scored his 10th international goal and at 20 years, 189 days, broke the American mark for youngest to double-digit goals, set in October 2010 by Jozy Altidore at 20 years, 337 days.
Pulisic had not scored for the Americans since the October 2017 loss at Trinidad and Tobago that cost the U.S. a World Cup berth.
Chelsea agreed in January to buy Pulisic from Dortmund for €64 million and loaned him back to the German club for the rest of the season.
Information from the Associated Press was used in this story.