Billy Vunipola out of the World Cup, replaced by 37-year-old Nick Easter

England No.8 Billy Vunipola is ruled out of the remainder of the Rugby World Cup with a knee injury, with Nick Easter taking his place in the Red Rose squad.

Saracens No 8 Vunipola was initially rated “50-50” for this weekend’s crucial Pool A game against Australia at Twickenham after he suffered a knee injury during Saturday’s 28-25 defeat to Wales, but his tournament is now over after he underwent a scan. “We know he will make a big contribution”.

With 52 caps to his name he is the only surviving member of the 2007 squad that reached the final before losing to South Africa while he was also part of the ill-fated campaign four years ago in New Zealand. That was a reference to the potential bonuses on offer for England, and the comment was included in a post-tournament review that was leaked and published by a British newspaper.

Elsewhere in the squad, England are still sweating over the fitness of Courtney Lawes, Ben Youngs and Jonathan Joseph ahead of the crunch match against the Wallabies on Saturday.

If Vunipola and Morgan are ruled out and Wood is cited and subsequently suspended, England will be facing a crisis in the back row with Chris Robshaw and James Haskell their only recognised options in the position, although Sam Burgess has played at blindside flanker for Bath. “Now time to give my all for England Rugby from the stands”.

“He’s been involved in some big games in World Cups before and been successful. It’s very early still”, Lancaster said.

England announces its side for Australia on Thursday.