Fans have been protesting against the American owners recently, unhappy with off-field matters and in particular the club's debt.

Ferguson believes they have every right to voice their concerns but admits as far as his role is concerned, the Glazers have caused no problems.

"I'm never against protest," he told The Observer.

"It's everyone's right, there's no doubt about that.

"But my problem with it, being manager of Manchester United, is that I've got owners who have never caused me any bother.

"Any time I've asked for money they have given it to us."

Ferguson has been full of praise for Wayne Rooney recently as the striker's red-hot form has helped compensate for the departure of Cristiano Ronaldo last summer.

"What we're seeing now is a terror of a player," said the Scot.

"What he's got that he can't lose is an in-built hunger, in-built energy, in-built desire. Some people are born with these things."

The United boss also revealed that despite the protracted saga of his move to Real Madrid, Ronaldo remains on good terms with him.

"The only reason he was sold was because the boy fervently wanted to leave," said Ferguson.

"I got a text from him last week saying: 'I miss you so much'. I'd texted him to say happy birthday. He was 24. And he said he missed me, and 'thanks for all the kind things you're saying about me'. You appreciate things like that."