Chelsea have an agreement in place with Atletico Madrid to sign the 26-year-old midfielder on loan on deadline day.
The Blues have agreed to pay a loan fee of €5m and have agreed to a €35m option to buy figure as well as part of the agreement.
But with the transfer window shut, Chelsea are yet to confirm the deal and it has been claimed that it is still being held up due to pending paperwork.
Atletico Madrid are yet to sort out all the paperwork for Chelsea to sign the midfielder on loan this summer.
But Chelsea and Atletico Madrid will get another hour to sort out all the loose ends for the deal to go through for Saul to move to England on loan.
The Spaniard wants the move and Chelsea and his representatives have been racing against time to get the deal over the line.
Atletico Madrid are currently also tied up in an agreement to sign Barcelona forward Antoine Griezmann, who is set to return to the club.
There are claims in Spain that the Griezmann move is dependent on Saul moving to Chelsea in the coming hour.
