Benfica goalkeeper Ederson was at Manchester City's training ground on Tuesday but official announcement of his £35 million transfer will have to wait.
A third-party issue means confirmation of City's second signing of the summer will not come until Wednesday at the earliest.
Benfica confirmed negotiations with City for the Brazilian goalkeeper to the Portuguese stock market on Tuesday afternoon, but stated a deal was not yet finalised.
Fifty per cent of the total transfer fee will go to Benfica, with the remaining 50% going to Ederson's former club Rio Ave, and 20% of that cut going to football agency Gestifute.
Goal revealed on Saturday that City had been working on a deal for the Brazilian goalkeeper for several months and were confident of making an announcement shortly after Benfica's Taca de Portugal final on Sunday.
Benfica beat Vitoria Guimaraes 2-1 and Ederson revealed during the post-match celebrations that he had "probably" played his final game for the club.
Having flown to Manchester after Sunday's game the goalkeeper visited City's training ground on Tuesday to complete a medical and sign a five-year contract.
The 23-year-old was also photographed and interviewed by the club's media department ahead of his official unveiling.
Ederson is set to become the most expensive goalkeeper in history, in pound sterling at least, as his £35m fee will eclipse the £33m Juventus paid Parma for Gianluigi Buffon in 2001.
The figure in euro, however, is significantly different, as Juve paid €55m for Buffon, whereas City will pay around €40m thanks to current exchange rates.
Regardless of any potential records, City believe they will be getting value for money from Ederson.
The Blues are aware that the best players in Europe will move for big money this summer and the club are keen to get their top targets in as quickly and smoothly as possible.
Club insiders believe the £43m they paid for Bernardo Silva will come to be regarded as a bargain, and that also goes for Ederson, whom Pep Guardiola has identified as his top choice.
Guardiola believes the Brazilian has the ability and temperament to slot straight into the City line-up next season.