The 21-year-old left-back spent last season at Burnley and played a big part in getting them promoted to the Premier League.
Vincent Kompany has remained keen on getting Maatsen back at Turf Moor all summer but it has taken until deadline day to work out an agreement.
It has been claimed that a deal is in place between Chelsea and Burnley for the left-back to move to Turf Moor on deadline day today.
However, Burnley are now facing a tough job in convincing Maatsen to accept the transfer by the end of the night.
Despite having had a successful loan spell at Burnley, he is reluctant to leave Chelsea at a late stage of the transfer window.
With Marc Cucurella staying at Chelsea, Maatsen is likely to be third choice left-back at the club if he stays at Stamford Bridge.
Burnley are hopeful that they will be able to convince the player to return to the club in the coming hours.
