Erik ten Hag has been urged to get hold of Cristiano Ronaldo and make clear his role at Manchester United or consider stronger disciplinary action.
The forward has been the main talking point this season at Old Trafford, even when he's not been on the pitch. Ronaldo made moves to quit the club in the summer less than a year after returning but couldn't find a suitor and remains a United player.
Ten Hag has only used him sporadically, handing the Portuguese star just his second Premier League start in nine games on Sunday.
Largely he's been used from the bench, but it was his reaction when he was bought off against Newcastle United that grabbed the headlines.
The Dutchman, who is still in the infancy of his tenure, has been encouraged by former Liverpool and England midfielder Danny Murphy to lay down the law to Ronaldo - making it clear that he will not be playing 90 minutes every week and refusing to accept negative reactions that undermine his authority.
Murphy said on TalkSport : "He's (Ronaldo) allowed to (act negatively) - that's the problem. I think the manager should be having a conversation with him before each game, he deserves that respect from any manager. It is a conversation where you go 'look, give me everything, you're probably going to come off after 70 minutes but I don't want the histrionics when you come off, does me no favours'.
"And if he does you bomb him, you've got to start creating a discipline at a club like Manchester United that everyone can follow. I'm not comparing (Pierre-Emerick) Aubameyang with Ronaldo, because they're not comparable in that respect, but he was a big figure at Arsenal.
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"Arteta gave him chance after chance and then went 'you know what, enough is enough, you're gone'. Now Ronaldo might be going in January off his own terms and that is up to him, but when you're in a club like Manchester United Ten Hag has got to take control of it quicker because it looks like he's got no control over him."
Ten Hag opted to bring Marcus Rashford on for Ronaldo on Sunday, although the forward did miss a huge chance to grab three points in stoppage time. The United boss explained his decision to haul off his No 7 insisting he must rotate his options.
He said: "We have to recover four games in 10 days and especially for the strikers, I want to keep them fresh. I want to keep them all fresh, we have to rotate because of some problems we have. [Anthony] Martial is not available in this moment, then Rashy [Marcus Rashford] was not well, so he did not have energy for the whole game."
