The 32-year-old centre-back was stretchered off in tears after just 12 minutes of his side’s 1-0 second-leg loss at the Wanda Metropolitano, with manager Arsene Wenger confirming he faces a lengthy spell on the sidelines.
“It doesn’t look very good, it’s his Achilles,” said Wenger.
“You can always hope for a miracle in the scan but the first signs don’t look very good.
“It looks that it could be ruptured but I am a bit cautious because nobody can say that just by looking at him. If he has a ruptured Achilles, his chances (for the World Cup) are non-existent. We will know more after the scan.”
The injury is a big blow to France coach Didier Deschamps, with his side to begin their World Cup campaign on June 16 against Australia in Kazan.
Koscielny has made 51 international appearances for France since making his debut in 2011 and has been a regular starter under Deschamps.
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