Ronaldo only signed a lucrative five-year contract with the Red Devils last summer but after emerging as the inspiration behind their Premier League and Champions League triumphs this season is now in line to be officially crowned the world's best player.

After taking his seasonal tally to a mindboggling 42 with the opening goal in Moscow on Wednesday, Ronaldo then survived the trauma of missing his effort in the penalty shoot-out as United overcame Chelsea to be crowned European champions for the third time.

Almost immediately, Real Madrid renewed their interest in the 23-year-old, triggering a withering response from Ferguson.

However, while the Scot is convinced Ronaldo will remain at Old Trafford this summer, he feels United must continue to make their presence felt in European competition if they are to keep the Madeira-born winger when the crunch really arrives.

"Real Madrid have no moral issues at all," said Ferguson.

"They think they can ride roughshod over everyone but they won't do it with us.

"Real Madrid are not the only club interested in Ronaldo. But the others are not saying so.

"Cristiano is 23 now. When he gets to 25 or 26 he will have a big decision to make. That will be our biggest task.

"How big we are then in terms of European trophies will be very important to this club."

Ferguson has repeatedly stressed the need for United to have more European Cups to their name.

This week's triumph has taken their tally to three but they still lag behind Ajax and Bayern Munich, who have four each, plus Liverpool with five and AC Milan and Real Madrid, who have seven and nine respectively.

Ferguson is confident the gap will narrow still further over the next couple of years, when he still hopes to be pouring scorn on the men from the Bernabeu, with club president Ramon Calderon a particular target.

Calderon has effectively alleging Ronaldo is remaining at United against his will.

Given General Franco's 40-year dictatorship was often at the benefit of Real in their battles with Catalan giants Barcelona, it is a comment the Manchester United manager is happy to submerge in sarcasm.

"Calderon makes that great statement 'Slavery was abolished many years ago'. Did they tell Franco that? Give me a break," said Ferguson.

"In terms of great clubs, Barcelona have far better morality than Real Madrid will ever have.

"The simple fact is Cristiano has another four years left on his contract."

It appears that Ronaldo would prefer to remain with United for at least another year, with the club keen to keep him for much longer than that.

Yet the suspicion remains his agent Jorge Mendes will demand more money this summer and if United refuse, as they have given every indication they will, it would be interesting to see what Ronaldo's stance would be.

Certainly it could be argued there are parallels between Ronaldo's position and the one Ferguson found himself in when the Red Devils declared their interest in the then-Aberdeen boss over three decades ago.

"I had a lot of offers when I was at Aberdeen but I would only have left for Manchester United," he said. "They were my club.

"I had a chance to join Arsenal and Tottenham, plus Rangers twice.

"You do not get much bigger than that outside United. But it is how big we become that is important."

It does not appear the Spanish giants will abandon their attempt to lure Ronaldo to La Liga.

After all, David Beckham, Ruud van Nistelrooy and Ronaldo's good friend Gabriel Heinze have all joined Real from United in recent years.

Yet, while the Heinze deal was one that suited United totally given the player's often-stated desire to join Liverpool, Ferguson is happy to point out both Beckham and Van Nistelrooy had reached the end of their usefulness for the Red Devils, who do not let players go who they want to keep.

"It doesn't matter which player it is, the ones you want to keep you have to work hard for," he said.

"In the modern day that is a fact. It is not lost on Manchester United but it is not lost on Real Madrid either.

"Yes, we sold them Van Nistelrooy and Beckham but we did that because we wanted to."

ends