#2 Kalidou Koulibaly
Kalidou Koulibaly was signed by Napoli in 2014 for £5.25 million. However, under Rafa Benitez, he never really looked like a smart buy as he often gave up possession and was caught napping, ending a forgettable season with Napoli as they finished 5th in Serie A. 2015-16 would however be his season, with the Senegalese establishing himself as one of the best centre-backs in the league and helping Napoli finish runners-up last season.
Koulibaly stands a massive 6ft 5in and is known for his physical prowess who can intimidate and physically dominate strikers. The Senegal international is also versatile who can play in any position across the back line and also as a defensive midfielder if need be. He is also excellent at recovering balls and is not afraid to put in the perfectly timed tackles as he often did last season.
The Senegal international would come at a massive £50 million pounds and though Chelsea’s interest in him has decreased in recent times, one never knows when Roman Abramovich would take out the moolah from his pocket and go on and sign the defender.