The 30-year-old striker comes to the Stadium of Light from Turkish club Trabzonspor, although he is no stranger to the Premier League.
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N’Doye started last season with Lokomotiv Moscow, but joined Hull City on the final day of the 2015 January transfer window. He scored five goals in 12 appearances for Hull, but left for Turkey when they were relegated to the Championship.
Sunderland boss Sam Allardyce is hoping that N’Doye’s experience in the Premier League last season will help him “hit the ground running.”
A Senegalese international, N’Doye will not be able to play this weekend at Tottenham as his papers are finalized, but should be ready to face Bournemouth on January 23.
N’Doye will give Jermain Defoe more support up top, as Sunderland needs goals to try and stay up in the Premier League. Defoe has scored nine goals on the year, while the club’s second-leading scorer Steven Fletcher has just four.