Napoli coach Carlo Ancelotti has defended his back four.
Napoli conceded eight goals in their two preseason friendlies against Liverpool and Wolfsburg, before shipping another three at Sampdoria in Serie A last time out.
Ancelotti said, “To say Napoli's defence is poor because we've conceded many goals isn't reality.
“The team, in our three games, played well from a defensive standpoint. Chiriches? We'll be without him for a while, but we'll find solutions.
“Mertens or Milik? I haven't made a decision. They're in the same condition. They came back quite tired yesterday.
“I want to see today's training session before I make one. A run of very important games begins. We respect Fiorentina, but we must grow in terms of self-esteem.
“Ghosts of the past? For my part, no, but I don't believe there is one for the players."