Belgium right-back Anthony Vanden Borre will miss the rest of the World Cup after breaking his ankle during Thursday’s 1-0 win over South Korea.
Vanden Borre finished Belgium's final Group H game with a suspected twisted ankle but hospital tests revealed he had a fractured fibula.
The 26-year-old is not a first-choice starter at the tournament and played against South Korea as cover for Toby Alderweireld, who was rested along with several other players.
Belgium manager Marc Wilmots said: "Anthony won’t play again at this World Cup but will stay with our team."
Belgium also have fitness concerns over captain Vincent Kompany and Thomas Vermaelen ahead of Tuesday’s last 16 -clash with the USA in Salvador.
Kompany has not trained since Wednesday due to a groin problem, while Arsenal centre-back Vermaelen only started running on Thursday after injuring his thigh against Russia.
To add to Belgium’s defensive woes, defender Laurent Ciman, who was a substitute for the Russia game, has had a groin injection and is also doubtful for the USA showdown.
Wilmots said: "I hope to have these three players back. We'll see on Monday, the day before the match."
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