Saracens’ stroll to victory over Sale marred by Billy Vunipola injury

• Saracens 41-13 Sale• England No8 leaves field in distress after catching knee in awkward positionIt is innocuous afternoons such as this – a routine maximum haul at home for the European champions – that can inflict the most damage. Billy Vunipola left the field just before half-time in evident pain, unable to put any pressure on his right knee. With England due to gather in Oxford on Sunday for a three-day camp in advance of the November internationals, the timing is particularly unfortunate, for player, club and country. And all this after a return last week from the injury that had cost h…