Gio Reyna was substituted early on during the United States' limp 0-0 draw with Saudi Arabia on Tuesday, dealing them an injury scare less than two months before the start of the World Cup.
The Borussia Dortmund winger, who is expected to play a key role for Gregg Berhalter's men in Qatar, bowed out after just half an hour of the team's final pre-tournament friendly in Murcia, being replaced by Paul Arriola.
The teenager's departure will have set alarm bells ringing, particularly given he missed much of last season after suffering several muscle injuries.
A statement on the national team's social media channels moved to allay those fears, however, indicating the Dortmund man was replaced as a precautionary measure after experiencing "muscle tightness".
Berhalter's side had started brightly in Spain, with Tyler Adams going close from distance, but Saudi Arabia missed the best chance of the first half when DeAndre Yedlin – who was also later substituted through injury – made a last-ditch block to deny Hattan Bahebri.
Jesus Ferreira could only manage a tame attempt when presented with the USA's best opportunity of the second half, and they will enter the World Cup in disappointing form, having suffered a dismal 2-0 loss to Japan last week.