Chelsea and Wigan Athletic are still haggling over a fee for Victor Moses.
The Daily Mail says Wigan's demand that Chelsea pay £7million of Moses protracted £10m transfer fee up front is the key stumbling block towards the completion of a deal.
Moses - who will net in the region of £40,000-per-week if his move to Chelsea goes through - is desperate to quit the Latics.
But Chelsea are keen to pay a smaller initial payment with the rest of the few made up in performance related add ons.
Talks between both club's are ongoing and a compromise is expected to be reached to pave the way for Moses return to London.