Jornal de Notícias says Liverpool are monitoring the situation of Diaz with a view to bringing him to Anfield during the upcoming January transfer window.
As a result, the Reds are rumoured to be preparing an official bid for the 24-year-old, though they will not go unchallenged for his signature.
Klopp's side will have to fork out £67m if they're to land the Colombia international in January.
Need a VPN? Or seeking to switch? Then support Tribal Football by clicking here to sign up with our official partners NordVPN. Not only will you receive the best VPN experience, but also great discounts by signing up via Tribal Football. Thanks for your support!