By GARY FITZGERALD

Injury prone: Billy Vunipola

Faith: Alex Sanderson

BILLY Vunipola must “keep the faith” if he wants to win his personal battle with a series of confidence damaging injuries.
Saracens forwards coach Alex Sanderson has urged the crocked No.8 to work hard and stay mentally strong in order to overcome his latest setback.
Vunipola, 25, whose South Africa tour ended early due to a second fracture to his arm, has endured an injury ravaged 21 months which has also included a series knee problem and a hamstring injury.
Having seen another England favourite Manu T...