Franco Baresi.
Paolo Maldini, is close. He is a long standing professional with alot of experience, but it terms of him best the "best" defender; Baresi was better.
He was quick. He coulda read the game extremely well. He was could play in any position in the backline. Maldini can play left back or in the middle; but he would be weak at a right back position. Baresi was an ALL ROUND stand out. Simply the best of all time.........