France captain Antoine Dupont said Sunday he had torn the cruciate ligaments in his right knee in the Six Nations victory over Ireland.

Dupont sustained the injury in the first half of the 42-27 win in Dublin on Saturday when he was caught in a ruck with Irish lock Tadhg Beirne appearing to land on him.

"Torn cruciate ligaments," Dupont said on Instagram. "It's the start of a new challenge, I'll see you in a few months on the pitch."

Dupont, who accompanied his post with a flexed bicep emoji, added: "The heart hurts even more than the knee when you have to leave your mates before the last hurdle.

"I am proud of what we accomplished yesterday and am with you with all my strength, you will do it," he said in reference to France's final match against Scotland on Saturday.

The manner of how Dupont suffered the injury left both Gregory Alldritt, the France No 8, and head coach Fabien Galthie seething.

Both claimed the scrum-half, widely considered to be the best player in the world, was targeted by Beirne, though, the referee Angus Gardner and the Irish interim head coach Simon Easterby begged to differ.

"When you return to the changing room and you see one of your best friends in that state it rips your guts up," said Alldritt.

France have cited Beirne and prop Andrew Porter, who they also claim is responsible for Dupont's injury as he drove through behind the second-row forward.

Dupont was attended by medical staff before they supported him as he limped off the field to be replaced by Maxime Lucu, the only back on the French bench.

Ireland interim coach Easterby said it was "just a rugby incident".

"This happens," he said. "It's just one of those things that unfortunately happens in the game."

France have to beat Scotland at home next week to secure the Six Nations crown.

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