LEEDS have been dealt a huge injury blow in their bid to beat the drop.
Javi Gracia's side currently sit just two points above the relegation zone with 11 games remaining.
Tyler Adams missed their 4-2 win at Wolves prior to the international break after picking up a hamstring injury.
The issue prompted Adams to pull out of the United States squad.
And according to the Mail, Leeds' medical staff have determined that the 24-year-old requires surgery.
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No timeframe has yet been put on his return to action.
The US skipper signed for the Elland Road club from RB Leipzig in a £20million deal last summer.
He has quickly become a key man in Yorkshire, starting 24 of Leeds' 27 Prem matches this term.
Gracia's men travel to Arsenal this Saturday as they continue their quest for survival.
In addition to Adams, Leeds could be without attacker Wilfried Gnonto after the Italian picked up an ankle injury on international duty.
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Azzurri boss Roberto Mancini said: "Gnonto is dealing with a sprain, I hope it is nothing to worry about."
Max Wober could also miss out after picking up a knock while playing for Austria.
The defender was injured during the first half of his country's 4-1 win over Azerbaijan.
