Manchester United captain Nemanja Vidic will be out until around Christmas it was revealed today.
The Serbian defender has been out of action since undergoing knee surgery in September, with an initial time-frame of eight weeks before he could return.
That would have seen Vidic back at the heart of United's defence by the end of this month, but Ferguson has said that date has had to be revised.
"I think we're talking around December for Vidic. Maybe around Christmas time," the United manager told MUTV.
Vidic has been beset with injury problems over the past couple of seasons, missing five months of the last campaign with cruciate ligament damage.
With Chris Smalling and Phil Jones also out at the moment, and with United having conceded two goals or more in their last four matches, the news represents a significant setback for the Red Devils.