Fabian Johnson could miss United States' upcoming World Cup qualifiers against Guatemala this month after he suffered a groin strain while playing for Borussia Monchengladbach.
Gladbach announced on Saturday that both Johnson and Raffael are set for spells on the sidelines after picking up injuries in Friday's 2-1 defeat.
No information was given on when the duo are likely to return to action but Jurgen Klinsmann's United States face Guatemala away on March 26 and at home on March 29, which leaves the 28-year-old little time to recover.
Sadly, both #Raffael and @FabianJohnson23 picked up injuries during #S04BMG: https://t.co/GoBAJWRKDY #fohlenelf pic.twitter.com/j1GQIaRSDb
- Borussia (@borussia_en) March 19, 2016
A statement on Gladbach's official website read: "Raffael and Fabian Johnson are both set for a spell on the sidelines after picking up injuries in the 2-1 loss to Schalke 04.
"Raffael, who received treatment immediately after the game, suffered a pulled hamstring in Gelsenkirchen. The diagnosis was confirmed following an MRI scan.
"Fabian Johnson underwent the same examination, revealing a groin strain for the USA international. Both players will be sidelined for the time being."
Victory for Schalke on Friday saw the Royal Blues overtake Gladbach in the Bundesliga, with Andre Schubert's men dropping to fifth.