Newcastle United have confirmed that midfielder Jack Colback will be sidelined for up to six weeks with a knee injury, following further scans and assessment by the club on Thursday.

The 26-year-old was injured early in the second half of Sunday's Wear-Tyne derby with Sunderland at the Stadium of Light, Vurnon Anita taking his place as the Black Cats clinched a 3-0 victory.

Reports had previously claimed that Colback could be out until the New Year, but a statement on the Magpies' official website confirmed that "the injury is not as bad as first feared".

The former Sunderland man has started nine of Newcastle's 10 Premier League games this season, taking his appearance tally to 48 in all competitions since arriving from the Black Cats in June 2014.