Leeds midfielder Tyler Adams has had hamstring surgery and faces an extended period on the sidelines, the PA news agency understands.
Adams, who missed the Premier League win at Wolves 10 days ago, has undergone a “non-invasive” procedure after consulting a specialist.
Leeds are assessing the 24-year-old USA skipper’s progress, but are still waiting to learn how much of this season’s run-in he is likely to miss.
Adams has played a key role for Leeds since joining from RB Leipzig in July for a reported £20million, starting in all of his 24 league appearances, and his absence is a major blow in their bid to avoid relegation.
They sit 14th in the table, two points above the relegation zone, and play at title-chasing Arsenal on Saturday.
Leeds head coach Javi Gracia said prior to his side’s 4-2 win at Wolves: “We know, all of us, that Tyler is a key player for us, but we have to manage with the squad we have. We have other players ready for the next game.
“He is different to others. There is no one like Tyler because all the players are different with different features and skills they have, but in this case we have other players ready as you can see in the last games we’ve played.”
Adams skippered the USA at Qatar 2022 – they lost 3-1 to the Netherlands in the last 16 – and missed Saturday’s 7-1 win against Grenada and Monday’s 1-0 win against El Salvador in the CONCACAF Nations League.