Kalidou Koulibaly
https://www.youtube.com/watch?v=e2b20E7YWTc
With Chelsea in desperate need of a strong, solid centre half, they should look no further than Kalidou Koulibaly.
The Napoli defender has everything to be a top Premier League central defender; he is strong, powerful, pacey, great in the air and, crucially, consistent.
A good centre-half is notoriously difficult to come by, and in Kalidou Koulibaly you have a defender that could strengthen the Chelsea defence for years to come.
Crucially, the Senegalese defender typically plays on the left hand side of a defensive pairing; the role that John Terry currently plays for The Blues.
A natural left-sided central defender is rare, with most favouring a role on the right.
With JT likely in his last year with The Blues, Koulibaly could be the perfect man to replace him.