Vunipola has knee surgery, faces 6 Nations fitness battle

LONDON (AP) England No. 8 Billy Vunipola faces a battle to be fit to play any part in the Six Nations after undergoing knee surgery that has ruled him out for at least three months.

Vunipola was forced off with a torn cartilage during Saturday's 27-14 victory over Argentina at Twickenham.

England head coach Eddie Jones says ''Billy's been absolutely fantastic for England over the last 11 months and we wish him a quick recovery.''

The Six Nations starts in February.