Billy Vunipola is out for four months and will miss the Six Nations after injuring his knee in England's 27-14 victory over Argentina over Argentina on Saturday.

The Saracens’ No.8 was taken off after 38 minutes of the game and now faces a race against time to be fit for the British & Irish Lions’ tour to New Zealand next summer. He underwent surgery earlier today and is expected to miss the next four months, which not only rules him out of next Saturday’s Test with Australia that could cap a year unbeaten under head coach Eddie Jones, but also the entire Six Nations campaign in February and March next year.

Vunipola, 24, has been one of England’s stand-out performers since being made one of three England vice-captains, along with Owen Farrell and Mike Brown under Eddie Jones.

He attempted to carry on, but when he got back to his feet he was in obvious pain and an immediate decision was taken to replace him, with Vunipola eventually requiring a cart to take him off their field.

England head coach Jones said: “Billy’s been absolutely fantastic for England over the last 11 months and we wish him a quick recovery.

“But where there is an injury there’s an opportunity for someone else.”

Nathan Hughes of Wasps is favourite to step in for Vunipola in Saturday’s game against the Wallabies after missing the game against the Pumas with a toe injury.

Vunipola took to Twitter on Saturday night to pray for good news on Sunday, but it was the complete opposite and England are expected to provide an update on his condition on Sunday night.