Sunderland are ‘very confident’ that one key player will sign a new contract this summer. Sunderland face much uncertainty this summer, with many clubs circling as they await for the transfer window to open. Reports have claimed that Sheffield United are preparing a £8 million bid for Anthony Patterson, while the Black Cats will expect to face stiff competition to keep hold of Jack Clarke for the third window in a row. The likes of Trai Hume, Dan Ballard, Pierre Ekwah and Dan Neil have all been linked with moves to the Premier League. However, Sunderland will be desperate to keep some of their…