Manchester United boss Sir Alex Ferguson has hinted at buying back Cristiano Ronaldo from Real Madrid.

The Sunday Express says the manager has maintained his close bond with the winger who developed into the best player in the world under Ferguson's tutelage.

Ferguson said: "Cristiano knows the value of Manchester United. That's the thing. What the players have got here is protection. They come to training every day and there is nobody here to disturb them.

"I don't think Real Madrid is an easy club to play for. There is a circus attached to it. There are often loads of fans and an intensive media always filming them."

He added: "You would like to think that one day he will come back, but you never know. I don't think he will stay at Real Madrid for life or anything like that.

"There will be other challenges and he is that type of player who welcomes them."