Borussia Dortmund midfielder Christian Pulisic will join the United States national team in Columbus, Ohio, next week if he recovers from an illness.
Pulisic, who doesn't turn 18 until September, has never played above the under-17 level for the U.S. but broke into Dortmund's first team in recent months.
He he has made six appearances since January, including in last week's Europa League win over Tottenham.
Pulisic received his first call-up to the senior team but was left off the final squad when he picked up a cold, ESPN FC's Doug McIntyre reported.
There had been speculation that Pulisic could join up with the under-23 team for their Olympic playoff against Colombia, but he will instead jump directly to the senior team.
The U.S. plays Guatemala in a pair of World Cup qualifiers this week, first in Guatemala City on Friday, followed by a home game in Columbus next Tuesday.
Pulisic remains eligible to play for Croatia if he so chooses until he plays in an official game for the U.S., and the second game against Guatemala would provide an opportunity to cap-tie him.
On Monday, his cousin and U.S. under-17 teammate Will Pulisic said he would train at Dortmund next season.