Manchester United insist Real Madrid were the ones to blame for the shock 11th-hour collapse of David De Gea's proposed move to the Bernabeu, according to Press Association Sport.
United and Madrid had agreed a deal worth £29 million for the sale of Spain goalkeeper De Gea on Monday, with Keylor Navas heading to Old Trafford as part of the agreement.
However, shortly after the deadline for Spanish clubs to confirm new signings, it emerged the necessary paperwork had not been lodged in time and the deal had therefore fallen through.
There was no sign of De Gea's name, nor that of Navas, on a confirmed list of La Liga transfers, which was published after the deadline had passed, leading to widespread criticism of Real in the Spanish media.
United have told Press Association Sport they uploaded the requisite documents to FIFA's Transfer Matching System before Monday's deadline at midnight local time in Spain.
Sources at Old Trafford have rejected reports in Spain that they submitted their paperwork after the deadline and claim they have a time-stamp from FIFA as proof.
United reportedly feel it was Madrid who failed to file their paperwork in time and believe they must take the blame for the deal's collapse.
Reports in Spain indicated the documents did not reach the Spanish league (LFP) office until 28 minutes after the deadline, while Sky Sports says La Liga did not receive any paperwork at all.
FIFA is reported to be looking into the details surrounding the collapsed transfer but it would be up to Real Madrid to make an appeal as it is the Spanish transfer window which has closed.
The only grounds for a successful appeal would be if the club could prove there was a failure in the administration involving the Spanish authorities.
There have never been any successful appeals regarding late transfers in the league's history and a source at the LFP told El Pais that there were no plans to make an exception.
In February this year, Levante lost an attempt to overturn a ruling that cancelled their loan bid for Fulham's Bryan Ruiz because they had missed the deadline for submission.
The Press Association reports that United officials question why Madrid left it so late to try to secure De Gea's signature.
They had made De Gea their top target earlier this summer following the departure of Iker Casillas to Porto and the two-time United player of the year himself was also determined to complete the move.
The 24-year-old, who joined United from Real's neighbours Atletico Madrid four years ago, hails from the Spanish capital and his pop star girlfriend Edurne Garcia also lives in the city.
But it was not until the final day of the window that Madrid made their first significant bid for the player.
The United board are said to be "relaxed" about the situation.
Although De Gea is yet to play for the club this season, United know they will now have a world-class goalkeeper available, should Louis van Gaal deem him mentally fit enough to play.
Meanwhile, the Press Association reports United have received offers for defender Marcos Rojo, but he wants to stay, while young striker James Wilson could go out on loan.