Tottenham are trying to salvage a deal for Pedro Porro after Sporting had a change of heart over the details of the transfer for the right wing-back.
Spurs had been making gradual progress on a move for the 23-year-old Spaniard with a medical tentatively scheduled for Monday. The player had said goodbye to the Sporting fans after the Taca de Portugal final defeat against Porto on Saturday night and was expecting to fly to London.
The Portuguese side were also closing in on a deal to sign former Arsenal full-back Hector Bellerin from Barcelona as a replacement for the outgoing Porro.