Oblak is unsettled at Atletico and is looking for a bigger, more ambitious challenge with a move to the Premier League at the forefront of his thinking.
The 27-year old, regarded by many as one of the top three goalkeepers in the world, is understood to have grown unhappy at some of the decisions and direction taken by Atletico's sporting director Andrea Berta.
Ideally they could offset Oblak's fee by using Kepa as a makeweight but Atletico don't want to lose face with fans. They know Oblak is a huge favourite and should he leave they want it to be for a world record fee for a keeper.
They also want to add two defenders and a midfielder but a reliable keeper remains key to Frank Lampard's plans.