Wolverhampton Wanderers medical staff have confirmed that defender Willy Boly suffered a "serious" ankle injury in training over the weekend.
The Frenchman has been an indispensable member of the Wolves squad this season, making 16 appearances in all competitions since Europa League qualifiers commenced in July.
Boly recently scored a famous goal for Wolves in Europe, scoring a superb 90th-minute winner away at Besiktas earlier this month.
In a statement released on Saturday, head of medical staff Phil Hayward told Sky Sports News: "Unfortunately, Willy Boly sustained a serious injury to his left ankle in training earlier today.
"Initial tests show a fracture to his fibula, and he will undergo further imaging over the coming days to determine whether surgery is required or not."
Boly has not travelled with the Wolves squad ahead of their meeting with Newcastle United at St James' Park on Sunday.
Nuno Espirito Santo's side, currently 13th in the Premier League, could all but secure qualification to the Europa League knockout phases with a win over Slovan Bratislava next month.