Sunderland defender Titus Bramble is due to undergo knee surgery on Thursday which will sideline him for at least six weeks.
Bramble missed Monday's night's 2-2 Barclays Premier League draw with Everton with damaged knee cartilage, and manager Steve Bruce admitted afterwards that it was likely he would need an operation.
A club statement said: "Sunderland defender Titus Bramble will go under the knife (on Thursday) to repair damaged cartilage in his knee. The 29-year-old was admitted to hospital to repair the injury, which was sustained in training recently."
The news will come as a huge blow to Bruce, who has seen his bargain summer buy from Wigan quickly win over his doubters.
Bramble's arrival did not meet with universal approval, with some fans remembering his error-prone days with derby rivals Newcastle rather than they way in which he rebuilt his career under Bruce in the north-west.
He missed only one of the club's first 13 league games, and that through suspension after he was sent off for two bookable offences during the 5-1 defeat by the Magpies on October 31.
He now faces a spell on the sidelines until the new year with Bruce indicating he will be out for "at least six weeks".
His place was taken on Monday evening by Anton Ferdinand with Ghana international John Mensah also sidelined by a shoulder injury.
Meanwhile midfielder Andy Reid's loan spell at Sheffield United has been extended until January 3.
The 28-year-old Republic of Ireland international initially joined the npower Championship club on a month-long emergency loan deal. But having impressed during his three starts to date for the Blades, he will remain at Bramall Lane until the new year.