Ferguson offered his insight into the Roanldo-Messi debate ahead of the El Classico tie, with the winners set to face United following their 2-0 win over Schalke in the first-leg in Gelsenkirchen.
High flyer: Ferguson still prefers Ronaldo (pictured) to Messi
The United boss who will be at the Bernabeu, told the club's official website,
'Well, I had Ronaldo here as a player and I think he is the best player in the world.
'He can play with both feet, he has fantastic skill, strength and bravery, and he's a greater header of the ball. But Messi is an absolutely fantastic player also.
'It depends on how you view your player.The fact that I had Ronaldo here so long, I know him well. I saw how hededicated himself in training sessions to becoming the best player in the world and so that would weigh heavily on my view of him as a player and as a person.
'It's difficult to choose between the two, it's the toss of a coin.
Heaven sent: Messi has won several plaudits including high praise from Ferguson
However Ferguson was full of praise for the Argentine international adding:
'But you look at the boy Messi and you know that he's a serious player. He loves playing football. He's as brave as a lion because he will always take the ball in any situation. They are different types of players but there's no doubt both provide a fantastic end product.'
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