Former Manchester United striker Dion Dublin says his old gaffer Sir Alex Ferguson should let Cristiano Ronaldo leave if his heart isn't at Old Trafford.

Dublin said: "Ronaldo is one of the best players in the world and Sir Alex wants him at United. He will do his utmost to keep him.

"Ronaldo is now how Thierry was for Arsenal. When he wanted to score he would do. Ronaldo can just turn on the burners and get the goal. He is that good.

"Sir Alex will sit Ronaldo down and sort something out. But if your heart's not in it and you're not going to work 100 per cent on a Saturday then I wouldn't want you."