Besides the uncommon biographical circumstances in which the edition of Los diarios de Emilio Renzi was prepared, its outstanding feature can be said the renewed passage from a biographical identity (Ricardo Piglia’s) to a fictional one (Emilio Renzi’s). This slide of identities, already present in Piglia’s other works, finds here a more including and posthumous version. The article analyzes some devices on that issue, their semantic effects and their conexion with other narrative strategies. Changing the name’s significant strengthens the main axis of the litterary project and emphasizes the semantics of the previous books.