United, who were treated to another verbal volley on the subject of their No 7 from the Real Madrid president Ramon Calderon, said the operation he underwent in the Netherlands yesterday had been a success. But it will be at least a month before Niek van Dijk, the Dutch ankle specialist who operated on the 23-year-old, can assess when he will be ready to return to action.

Van Dijk operated on the Portuguese winger at the Academic Medical Centre in Amsterdam. "Initial indications are that the procedure was successful," United said in a statement. "Cristiano will begin his convalescence under the direction of club medical staff and an estimation of his return to full fitness will be possible following review by the specialist in one month."

It is unclear whether the operation might dampen Real's ardour for a player whom Calderon indicated on Sunday would probably he playing his football in Manchester next season. But Calderon could not resist hammering away once more at United. They, he said, should be "happy and proud" to let Ronaldo leave the club. "I think that it's the desire of the player [to join us], but, of course, Manchester shouldn't be angry," Calderon insisted.

"We can't be blamed if nearly every player wants to come to Real Madrid. If I was Manchester United, I'd be happy and proud to be able to negotiate such a transfer for one of my players. Everything would be a lot easier if United realised that they could pull off the transfer of the century."