Aston Villa boss Steve Bruce has warned that "anarchy" could ensue at Manchester United if the feud between Paul Pogba and Jose Mourinho is not resolved.
Mourinho, who openly declared that Pogba has been stripped of the vice-captain's role earlier this week, was also seen in a heated discussion with the player during training before Saturday's defeat to West Ham United.
Speaking to reporters at a press conference, Bruce said that there must be "respect" between the pair if United are to succeed this season.
"Let's not kid ourselves, to a certain degree, player-power has always been there," the manager said. "But there has to be respect between any player and manager.
"I worked under the master, Sir Alex Ferguson. He had that respect. As players, we didn't always like it – but we respected him. And if that relationship doesn't exist any more... well, the lunatics will be running the asylum.
"It becomes a free-for-all. One person has to be accountable because, if that's not the case, I can guarantee that the club – and that's any club, not just Manchester United – will have problems. It could be anarchy."
United's next tie sees them host Valencia in the Champions League.
