Cannavaro is the best at anticipating. He's such a beast in anticipating passes. In Madrid this isn't as effective, because defences in La Liga frankly do not work as well as units, compared to Serie A defences. So no cover and no teamwork, if he intercepts a pass, he leaves space open. You can't play two anticipating cb's next to eachother, you need someone to cover the gaps.
Just look at this. amazing.
http://www.youtube.com/watch?v=yMwr...eb.co.uk/forums/showthread.php?t=6163&page=48
This only works though, when you have a cb covering, more of a say 'standing' cb. At juve, Cannavaro had Thuram and Kovac and for Italy, he had Nesta. Nesta takes the lead of the defensive line, guide his teammates, has dialogues with the goalkeeper (to find the most appropriate adjustements of the "axis") and cover those defenders who try to push foward. What makes Nesta greater than other, is he how he pushes the defensive line forward and keeps the gaps so close.
Both Cannavaro and Nesta are great, but different.
I think what makes Chiellini and Legro work so well, is that they too are different and complement each other well. Chiellini also pushes more forward and anticipates, while Legro covers from the back. Andrade and Criscito did not complement eachother well.
Sorry for taking this a bit far

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