Sunderland forward Duncan Watmore is set to miss the rest of the season after scans revealed a cruciate ligament injury suffered in Saturday's 2-1 victory over Leicester City.
Watmore, 22, was stretchered off after a clash with Leicester's Christian Fuchs during the win over the Foxes at the weekend.
He has since visited a specialist in London and is now facing an extended period on the sidelines.
The club said in a statement: "Sunderland boss David Moyes has confirmed that Duncan Watmore is likely to miss the rest of the Black Cats' season following the results of his scan on Monday. Results from the scans revealed Watmore has suffered cruciate knee ligament damage.''
��Duncan Watmore has been ruled out for the rest of the season.
Get well soon, roadrunner!
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- Sunderland AFC (@SunderlandAFC) December 6, 2016
Watmore's absence will be a significant blow for Moyes, who is already without Paddy McNair, Lynden Gooch and Lee Cattermole for the long term.
Watmore has started 11 games for Sunderland this season and proved a major factor in their recent revival, which has seen them win three of their last four games to move off the bottom of the Premier League table.