Sunderland have confirmed that Wes Brown will miss four to five weeks after picking up a knee injury during the team's defeat to West Ham United last month.
The defender limped off at Upton Park after an awkward landing, ruling him out of this weekend's Tyne-Wear derby against Newcastle United.
Head coach Dick Advocaat told the club's website: "It looks better than we thought before but it will still be difficult to bring him back this season, so hopefully at the end but the doctor said it takes four or five weeks."
Sunderland are just a point clear of the relegation zone heading into the final eight games of the Premier League season.
