It began when Ronaldo dismissed suggestions from Mourinho that Manchester United had benefitted from refereeing.

"I really don't want to be dragged into Mourinho's complaints over referees - everybody knows how he is," Ronaldo said.

"He always has to say something because he can't admit his failures.

"We have to think about the game in Milan. We have a good squad and I think we are on course."

Mourinho handed in his response speaking to RTP TV: "If he says it's a lie Manchester United have conceded some penalties this season which have not been awarded against them he's lying.

"Ronaldo is a great player, perhaps the best in the world. But he needs to be mature enough to accept you cannot argue against facts.

"And if you lie then you may never reach the level which he aspires to as a footballer."

Manchester United assistant coach Carlos Quieroz - another Portuguese - also got himself into the act, suggesting that the Chelsea coach was up to his usual tricks.

"Mourinho has his own style, he always tries to divert everyone's attention to the points which are convenient for him," he said. "These are his tactics and that's the way he is."

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