#1 Kalidou Koulibaly (Napoli)
The first pick on our list today is a monster created by Chelsea manager Maurizio Sarri himself, during his time at Napoli - Kalidou Koulibaly.
The French-born Senegalese International has been linked to every top European club in the last two seasons. However, a reunion with Sarri could be a big factor in luring him to the Premier League.
The 27-year-old has been Serie A's best defender in the past few seasons and has tormented every striker in the Italian league by being a mountain in front of the goal.
If Chelsea are to secure Koulibaly, they can finally have their own reply to Liverpool's Virgil van Dijk and Manchester City's John Stones and Aymeric Laporte.
Koulibaly is definitely the player who can bring back the glory days for the back four of Chelsea. He is someone who can make Chelsea a defensive superpower once more