France centre Wesley Fofana's participation in next month's Six Nations looks in doubt after the Clermont player suffered a possible Achilles injury in a Champions Cup game against Exeter on Saturday.
"We'll have to see after the medical checks but it does not look good at all," Clermont coach Franck Azema told BeIN Sport after his team's 48-26 win in their final Pool 5 game.
Fofana, one of France's most highly rated players, sustained the injury on his own at the end of the first half.
He was unable to put his left foot on the ground as he left the pitch.
France start their Six Nations campaign against England at Twickenham on February 4 and play Ireland on February 25.