N'Diaye only joined Sunderland in January, from Turkish Super Lig outfit Bursaspor, and he made 16 appearances in the second half of the season.

But he failed to make a significant impression on Sunderland manager Paolo Di Canio, who has signed midfielders Emanuele Giaccherini, Cabral, El-Hadji Ba and David Moberg-Karlsson in the close-season.

Sunderland confirmed the deal with a brief statement on their official website.

The 23-year-old will now link up with an Eskisehirspor side who finished eighth in the Super Lig last season.

N'Diaye is a France youth international and has represented his country at Under-21 level on one occasion.