Brazil: Gilmar, Nilton Santos, Djalma Santos, Falcão, Pelé, Garrincha and Romário(or Ronaldo).
Argentina: Passarella, Maradona and Di Stefano.
Chile:Elias Figueroa
Yep, I'd have mentioned Zico and Carlos Alberto too.
No thought on Roberto Carlos, often called the greatest ever left back?
:-)