FIFA will go into an emergency committee meeting in Zurich today to rule whether Arsenal's controversial FA Cup re-match with Sheffield United, scheduled for Highbury tomorrow night, can go ahead.
And the stunning announcement that the unique fifth round re-match is still in doubt leaves Arsenal and the Football Association fearing chaos and recrimination if it is suddenly kicked into touch by the game's world governing body.
All tickets for the 38,500 repeat match have been sold - at half normal prices - and all police and security arrangements made following the FA's instant decision two weeks ago to sanction Arsenal manager Arsene Wenger's offer that the game should be restaged after the Gunners' so-called "unsporting" goal which beat United 2-1.
On Saturday , though, FIFA's general secretary Michael Zen-Ruffinen, who was at the annual meeting of the International Board in Cardiff, revealed that the English FA have been asked to supply clarification of the FA Cup competition rules which enabled them to act in an unprecedented situation.
He explained: "Everyone is in agreement that no law was broken when Arsenal scored their second goal. The referee was perfectly entitled to award it and we have to consider whether the rules of the competition have been adhered to in granting a replay."
There is a suspicion that FIFA are merely sabre-rattling and wanting to underline that they have the ultimate power over all decisions made by national associations.
And the FA have expressed their confidence that the re-match will still go ahead.
Spokesman Steve Double said: "We have consulted our lawyers over the rules of the competition and they tell us that the principles stand up."
David Davies, the FA's interim chief executive, who sanctioned the re-match in accord with FA Cup competition chairman Terry Annable, within an hour of Wenger making the offer public last week, said: "The FA Cup is in the sole ownership of the Football Association and there is no reason to think the game won't go ahead."
Davies was in telephone talks yesterday with Arsenal vice chairman and FA councillor David Dein who backed Wenger's rematch gesture, which has already been saluted as an act of great sportsmanship by leading officials of FIFA.
However, if the re-match plan is vetoed and the original result stands, Arsenal will go through to a sixth round home tie against either Derby County or Huddersfield Town on the original result.