Sergio Dest was forced off during the second half of Barcelona's Europa League win against Galatasaray, sparking fears that the U.S. men's national team star could miss this month's 2022 World Cup qualifiers.
The defender would have been expected to play a part in the final stretch of qualification for the end-of-year tournament after completing club duties with Xavi's side.
But he was forced to leave the pitch after the break in Turkey with what looked to be a hamstring problem, throwing his potential role into doubt until the depth of his injury is known.
What happened?
Dest started in defence for the Blaugrana on the road in Istanbul and had played almost an hour before a sliding challenge on Kerem Akturkoglu looked to leave him in discomfort.
He was treated on the field by club medics and shortly left the pitch afterwards clutching his hamstring, with Ronald Araujo brought on to replace him.
The defender was later spotted being carried in a piggy-back and now both Barcelona and the USMNT face a nervy wait to discover the extent of his problem.
What was said?
"It's not great news," said U.S. men's national team boss Gregg Berhalter. "The initial diagnosis, it seems to be a hamstring injury, but we're gonna get the final details tomorrow.
"We may need to replace him and we've already identified candidates to replace them and we're already prepared to speak to them first thing tomorrow."
Berhalter added that any replacement would likely be a left back, with Reggie Cannon and DeAndre Yedlin providing cover at right back with just Antonee Robinson and, potentially, Kellyn Acosta on the left.
Who do USMMT play?
Any potential lay-off for Dest - even a short-term one - is likely to spell serious problems for his prospects of featuring for his country in their all-important trio of games later this month.
Though very much in the box seat to qualify for Qatar 2022, with their fate still in their own hands, there remains the possibility still that the USMNT could miss the automatic cut entirely.
They travel to Mexico and Costa Rica, with a home clash in Florida against Panama sandwiched in-between the two.
The U.S. will already be without Weston McKennie, who will miss the rest of the season with Juventus during an injury of his own.
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