FIFA has reportedly rejected Leciester City 's application to register Portuguese midfielder Adrien Silva after the Foxes missed the 11pm deadline by 14 seconds.
The BBC claims Leicester will appeal the decision, with the £22m deal with Sporting Lisbon now up in the air.
The football Association are expected to help Leicester with the case, with the Foxes now short a central midfielder after selling Danny Drinkwater to Chelsea close to the deadline.
A Leicester spokesman told the BBC: "We are working with Adrien and Sporting Clube de Portugal to overcome some issues relating to the player's registration and exploring all options to find a resolution."
Huddersfield Town host Leicester in 10 days time and Craig Shakespeare's side will hope to have the deal done in time for Silva to be made available.
West Brom have offered former QPR midfielder Karl Henry a chance to train at the club.
The 34-year-old is a free agent having been released by Rangers in July after four years of service.
And the Birmingham Mail understand Tony Pulis has offered Henry the chance to train with the Baggies to keep his fitness up until he finds a new club.
Our sister paper also understands however, that the combative midfielder will likely not be offered a contract at the Hawthorns.
Ghanaian striker Majeed Waris was left "disappointed" after a move to the Premier League broke down over the transfer window.
The Lorient forward looked set to join a Premier League outfit in the last window, with Burnley and West Ham interested, but work permit worries reportedly scuppered any move - meaning the striker would remain in Ligue 1.
There were rumours that Waris was Burnley's first choice to replace the departing Andre Gray, but when complications over the work permit, the Clarets pulled out of the deal and opted for Town's Nahki Wells instead.
Lorient president Loic Fery spoke about the transfer to Ouest-France. He said: “The moment where it all got stuck was around mid-August. We were close, at that point, with some clubs, but there were complications. Then, in the last few days of the window, it was more the work permit issues that were worrying English clubs.”
Finally, Tottenham deadline day signing Serge Aurier believes he was not respected by former club Paris Saint-Germain.
The controversial Ivory Coast international made the switch to Spurs, claiming he rejected a new deal with the French giants because he was undervalued in Paris.
He told the CAF website: "I left the PSG who had offered me a new three-year contract for another adventure. I refused for various reasons.
"I want to discover another life because in Paris, I was not respected at my true value. We dwelt on many details, we thought more about something else than the footballer."