Cristiano Ronaldo |
The Portugal international was largely unknown when he joined the Reds in the summer of 2003, in a deal from Sporting Lisbon which cost around £12million.
Ronaldo spent six years at Old Trafford, helping United win the Premier League three times and the UEFA Champions League whilst he established himself as world class.
Real Madrid eventually paid a world record £80million to take him to the Bernabeu in 2009, and earlier this month his goal beat Barcelona to lift the Copa Del Rey.
There has been speculation, though, that the 26-year-old could make a sensational return to United, but Ferguson has moved to play down such a deal.
“It would be very difficult," said the Reds boss. "He had a great time here, but he is at a great club now too. We got him as a kid and he went to Madrid a man.”