Koke, 23 was on Chelsea’s summer shortlist but they missed out on signing him then, which was another blow in what was a bitterly disappointing transfer window for the London side.
During the summer, they also missed out on John Stones and Paul Pogba and failed to add any first-team players to their ranks with players like Asmir Begovic, Baba Rahman and Falcao joining.
Jose Mourinho wants Koke to beef up a midfield that has been opened up too many times this season and has led them to already be 10 points behind leaders Manchester City after just 8 games.