Watford have signed Didier Ndong on loan from Championship side Sunderland until the end of the season.
And the Hornets have an option to sign the 23-year-old midfielder on a permanent basis in the summer.
Gabon international Ndong has played 54 times for the Black Cats since joining them for £13.6m from French club Lorient in August 2016.
Watford, who have loaned forward Isaac Success to Malaga, are 11th in the Premier League.
Sunderland are 23rd in the Championship, one point from safety.
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