Cristiano Ronaldo has had an operation on his right ankle and could miss the start of the season.

The Manchester United winger checked into a hospital in Amsterdam for the surgery and is not expected to play again for six weeks.

Johan Kortenray, press spokesman of the Academic Medical Centre in Amsterdam, said: "He arrived here yesterday evening to be examined. He'll be able to return home tomorrow."

It has been suggested the surgery could scupper any chance of him moving to Real Madrid.

The Spanish club's president Ramon Calderon has admitted there is little more that can be done to lure Ronaldo to the Bernabeu.

Calderon is due to meet David Gill, United's chief executive, and is expected to be issued with an official 'hands off' warning, marking the end of the Spaniards' protracted hunt for the Portugal international's signature.

Calderon said: "He (Ronaldo) must love Manchester. Once Manchester decide they want to sell and they tell us this, then we will say that we're talking about a transfer.

"But today that's not happening and therefore this is a situation that may end up as it is now, as nothing, and Cristiano Ronaldo will continue at Manchester next year.

"At the moment, that's the most likely scenario. They (United) don't want to sell so we can't do anything."

However, Calderon still appears to hold out some hope of bringing Ronaldo to the Spanish capital, adding there may be time to convince United to change their mind before the August 31 transfer deadline.

"Theoretically there's still time (for things to change). There are two months left until the end of August if Manchester get in touch with Real Madrid and make us an offer. But still we don't know if it would be possible to buy him even if they did want to sell."

According to Spanish reports, United had been set to test Real's resolve by offering Ronaldo for around £80 million - nearly £12 million more than the £67 million Real were reportedly prepared to pay.

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