Sunderland manager Martin O'Neill has confirmed that captain Lee Cattermole will be sidelined for two months with a knee injury.
The 24-year-old was expected to face a lengthy period of time away from the pitch after picking up the injury during the Black Cats' 4-2 defeat to West Bromwich Albion a fortnight ago.
It has now been confirmed that O'Neill will be without the midfielder for the club's vital busy festive schedule in the Premier League.
Sunderland currently sit just one point above the relegation zone in the league table.