Chelsea defender Marcos Alonso was due in Barcelona on Wednesday night.
Alonso was scheduled to fly to El Prat airport ahead of signing for Barca.
Sport says Barca directors Jordi Cruyff and Mateu Alemany are optimistic that the deal will go through.
Alonso will be closely following the possibility of player departures from Barça, as it would allow for his immediate registration.
All parties are confident of a deal being closed.