Sunderland have taken their summer signings tally to 10 by capturing Ondrej Celustka on a season-long loan.The 24-year-old Czech has joined the Black Cats from Turkish side Trabzonspor.
Celustka started his career with FC Tescoma Zlin before moving to Slavia Prague, for whom he made 41 appearances.
A short spell with Palermo followed before he headed to Turkey, while he represented his country at the 2011 Under-21 European Championships. The defender has 18 U21 caps to his name for the Czech Republic and featured for his country.
He joins Emanuele Giaccherini, El-Hadji Ba, Jozy Altidore, Vito Mannone, David Moberg Karlsson, Cabral, Modibo Diakite, Valentin Roberge and Duncan Watmore in joining Paolo Di Canio's side over the summer.