England face being without Harlequins flanker Chris Robshaw for their Six Nations campaign due to the injury he sustained for his club side earlier this week.
The 30-year-old damaged his shoulder in the 24-17 defeat to Worcester Warriors on New Year's Day, which required a scan to determine the full extent of the damage.
Harlequins revealed on Friday afternoon that they will be without Robshaw for this weekend's clash with Sale Sharks, with the former Red Rose skipper facing either "an extended period of rest and rehabilitation, or an operation" to rectify the problem.
It is potentially a major blow for England boss Eddie Jones, who admits that Robshaw has been his best servant since taking charge after the disastrous 2015 Rugby World Cup campaign.
Asked by The Sun who England's best player of 2016 had been, Jones said: "Chris Robshaw. He has been super. How he responded to losing the captaincy and conducted himself has been outstanding."
England kick off their Six Nations title defence with a meeting against France at Twickenham on February 4.