Sunderland take on Coventry City in the Championship this Saturday, but events during the week have added a new complication for the Black Cats. Coventry City sacked manager Mark Robins on Thursday to the surprise of the football world, given the success of his seven-year spell at the Sky Blues. Robins was the longest-serving manager in the division, giving Regis Le Bris and his coaching staff a deep back catalogue of information about the way Coventry would play on Saturday. However, with Robins gone, Le Bris will have to guard against the possibility of the cliched ‘new manager bounce’ often…