Christian Pulisic will miss USA's friendly against Wales on Thursday after being sent back to Chelsea from his national team camp for further treatment on an ongoing hamstring complaint.
The 22-year-old has been frustrated by an injury yet again this season, having made just three Premier League appearances for Frank Lampard's side so far in the current campaign.
The former Borussia Dortmund star was injured in the warm-up ahead of their 3-0 win at Burnley on October 31 and has not made the Blues squad since.
Pulisic nonetheless joined up with his national side ahead of the latest round of international fixtures, but USA boss Gregg Berhalter has now confirmed he will not feature in Swansea or against Panama on Monday.