How Man United dressing room turned toxic after Fergie: Brutal Van Gaal was hated by his players, Mourinho clashed with Pogba and Solskjaer's legendary status counted for little… So will Erik ten Hag suffer a similar fate?

Sir Alex Ferguson understood the vital importance of controlling the dressing room.

The legendary boss told Harvard Business Review: 'If the day came that the manager of Manchester United was controlled by the players - in other words, if the players decided how the training should be, what days they should have off, what the discipline should be, and what the tactics should be - then Manchester United would not be the Manchester United we know.'

In the same interview, Ferguson hinted that clubs such as Chelsea and Manchester City had changed managers so many times the players had total control of the dressing room.