The 29-year-old defender has secured a temporary switch to the Black Cats from Saudi club Al Hilal after moving from Rennes to the Middle East in 2012.
He is O’Neill’s second signing of the January transfer window after the Northern Irishman snapped up France Under-21 international Alfred N’Diaye last week.
“Kader is a player who will add to the overall strength of our squad and give us options. He will improve competition for places and we are delighted to welcome him to the club,” the Sunderland boss told the club’s website.
Mangane began his career in his native Senegal before spending six years in Switzerland. He played for Lens and Rennes in the French Ligue 1 before moving to Saudi Arabia in 2012.
Chris Winterburn (@Chriswin4): “Kader Mangane is a great signing for Sunderland, physical beast that will aid that struggling Sunderland defence massively – influential.”
Tom Bodell (@TBBodell): “Kader Mangane was imperious for me on #FM11 when I signed him for Liverpool. I hope he replicates that form for #SAFC.”
Pete McGirr (@bigpete1988): “Welcome Kader Mangane, another mountain of a man coming through the doors. Just what we need!! #safc #mangane”
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