The 22-year-old has signed a three-and-a-half year deal at the Stadium of Light, becoming O’Neill’s first signing of the January transfer window.
N’Diaye scored three goals in 37 appearances for the Turkish outfit after leaving Ligue 1 side Nancy in the summer of 2011.
O’Neill’s side are in 14th position after a string of impressive results, but the Northern Irishman is without captain Lee Cattermole, who is sidelined with a knee injury.
“Alfred is a strong, powerful young player and as such can offer us more strength in depth,” O’Neill told Sunderland’s website.
“He will give us options and I’m delighted that we have been able to bring him to the club.”
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