He was injured yesterday against Argentina
England's hopes of winning next year's 6 Nations have taken a blow with the news that Billy Vunipola is likely to be sidelined for up to four months.
The powerful number 8 picked up a knee injury during England's contentious win over Argentina at Twickenham yesterday.
A bad-tempered game saw two red cards, one for either team, as Elliott Daly was sent off early on after a ridiculous tackle on Leonardo Senatore while Argentina's Enrique Pieretto saw red for a disgusting stamp on Joe Marler.
The Saracens number 8 underwent surgery earlier today. Vunipola has become a pivotal cog in this English side as his powerful carries have often set the platform from which the team operate off.
England are due to play Australia next weekend and are currently riding a 13 match winning streak. Australia had their hopes of completing a grand slam tour dashed in Dublin yesterday when they were dispatched 27-24 by Ireland.
England welcome France to Twickenham on the opening weekend of the 2017 6 Nations Championship before travelling to Cardiff to take on Wales.
Two home games follow against Italy and Scotland before they head to Dublin on St. Patrick's weekend to take on Joe Schmidt's Ireland at the Aviva Stadium in the final game of the tournament.