#2 Kalidou Koulibaly (Napoli)
This deal is gonna cost Arsenal a fortune and they are going to face heavy competition from the likes of United, Chelsea and Juventus, and these clubs will be hard to outbid. The Gunners should definitely make a move for him as Kalidou Koulibaly is definitely the answer to all their defensive woes.
While the price may seem a little too much for the Gunners, the new Adidas kit deal, the departure of Aaron Ramsey, and Petr Cech retiring at the end of the season will relive them from their massive wages which should cover the transfer fee.
This season we've already seen what impact a defender like Van Dijk can make, as Liverpool have conceded the least goals this season in the Premier League. If Arsenal want to challenge for the title, they should go all in for Koulibaly and outbid any other offers.