Everton boss David Moyes is hopeful Portuguese midfielder Manuel Fernandes will be part of his squad "within the next 24 hours".
Fernandes played for Everton on loan last season
The 21-year-old arrived in Britain on Thursday with a view to completing a £6m move from Benfica.
Moyes said: "He had the first part of his medical and that will be completed on Friday."
The Everton boss added: "I would then expect him to become an Everton player within the next 24 hours."
The move will not been completed in time for the Portugal Under-21 player to acquire international clearance to be involved in Saturday's match at Reading.
He knows all about us and we hope he will be able to hit the ground running
Everton have also had to gain clearance from the Premier League over the signing because Fernandes is part-owned by a third party, the Global Sports Agency.
Under Premier league rules, England's top clubs are not allowed to field a player owned by a third party who would have the "ability materially to influence its policies or the performance of its teams".
Everton, it is believed, are only buying 50% of the player from Benfica, with third party companies owning the rest - however, they will have an option to buy out the rest of the player after a fixed period.
Fernandes spent the second part of last season on loan at Goodison Park and did enough for manager Moyes to want to agree a permanent deal for him.
Moyes said: "He knows all about us and we hope he will be able to hit the ground running when he arrives.
"He knows about us and what we do, he will give us a different option. We are playing with Lee Carsley and Phil Neville just now in the centre of midfield and he will give us more competition there.
"But he is a different type of player, with a bit more craft. At 21 he was a big player in the European Under-21 championships for Portugal and we are delighted to have him."