England’s Mako Vunipola could miss Six Nations with suspected ligament injury

• Prop was forced off in Saracens’ European Champions Cup win at Sale• 25-year-old could potentially be sidelined for 12 weeks with knee strainEngland prop Mako Vunipola’s participation in the Six Nations Championship is in doubt. Vunipola suffered suspected ligament damage in his left knee after being forced off in Saracens’ European Champions Cup win at Sale last weekend.The 25-year-old is expected to see a specialist in the next fortnight when the swelling on the knee subsides. It is thought his club Saracens have put a time frame on Vunipola’s potential absence as between four to 12 weeks.…