there are better defenders out there...Pepe and Alex...as well as Barzagli.
Heinze is a good defender but i think he is better at left back than centre back. Unless Deschamps wants him for left back which wouldnt make make sense considering we have chiellini and balzaretti already.
And then adding to that, we seem to like defenders who can play both full back and centre back..Grygera and Heinze could be useful in that sense with chiellini being that player also.