England lock Maro Itoje is set to miss “four to eight weeks” with his knee injury – but is expected to be fit for the start of the Six Nations.
The 24-year-old Saracens player chipped a bone in his knee on England duty and the problem is said to have worsened.
Saracens boss Mark McCall said there were no complaints about the way Itoje was handled by England and confirmed he would not require surgery.
England’s first match in the Six Nations is in Ireland on 2 February.
“From what I have been told, 100% he will be fit for the start of the Six Nations,” McCall told BBC Radio 5 live.
There had been a suggestion Itoje sustained the problem during England’s training camp in Portugal in October.
But he played in all four of England’s autumn internationals and also continued to appear for his club.