Portsmouth are facing liquidation after former owner Balram Chainrai's Portpin company withdrew its offer to buy the financially-stricken club.
The development - which happened hours after what was essentially a Portsmouth youth team lost 3-0 to Plymouth in the Capital One Cup - means the club's only potential source of salvation now appears to be its Supporters' Trust.
The Fratton Park club appeared to have escaped oblivion last week after administrator Trevor Birch confirmed that the remaining senior players he had needed to get off the wage bill had all left the south coast club.
That paved the way for talks with Portpin to continue, but on Wednesday Chainrai released a statement in which he confirmed that the Portpin bid was dead.
The statement, which criticised administrators KPF and claimed former Portsmouth players and management staff still had "huge football creditors' claims" said: "Portpin Ltd regrets to announce that it is withdrawing its bid for Portsmouth Football Club.
"Unfortunately, our efforts to save the club once more from extinction have hit a wall of rejection and been lacking co-operation from the administrator and other interested parties.
"We are not the ones who have caused the club to collapse, and we are not the ones to choose PKF as administrators. As history has recorded, we sold the club over a year ago after saving it from liquidation and unfortunately found ourselves again fighting to try and save the club from another liquidation."
The statement said that, through the six months of Portsmouth's latest administration, Portpin had "always had the club's best interests a heart - unlike many parties who were involved in the process".
It added: "We repeatedly encouraged the administrator to find a new, willing and able buyer to take over the club: unfortunately, he was unsuccessful in this job. Later, he approached us to be his safety net to save the club as he couldn't find a buyer. We agreed in the effort to avoid liquidation of the club."
The statement said the "last straw" had come when Pompey manager Michael Appleton admitted that, with no senior players, another relegation for the club, currently in League One, was inevitable.
"All of these facts have left us in a position that we no longer want to fight this battle," the statement said. "We have had zero support to save the club.
"Therefore, we formally withdraw our bid and our honest attempt at saving the club. We will sleep well knowing we did our utmost to save the club." However, the statement pledged assistance to "anyone, including the Supporters' Trust, to try and save the club in the coming days".
Birch called for urgent talks to be held in an attempt to determine whether the Trust's attempt to buy the club could succeed. He said: "We note Portpin's statement that it has withdrawn its bid for Portsmouth Football Club.
"In reviewing the options available to the club, we also note Portpin's offer to support any efforts to save Portsmouth in the forthcoming days.
"We are therefore urgently seeking a meeting with Portpin and the Pompey Supporters' Trust to determine if the Trust's bid can be brought to a successful conclusion."
The Trust said Pompey supporters had already pledged almost £2 million, with associate directors and individual investors counting for a further £1 million. Portsmouth City Council has agreed a £1.45 million bridging loan to the Trust in the event of a "commercial" salvation for the club failing to emerge.
The Supporters' Trust, SOS Pompey, called on Chainrai to "do the decent thing and accept the PST offer to purchase his charge on the club, and therefore walk away from Pompey, leaving the club in the hands of the people who will truly cherish it and ensure that it continues as both a business and a legacy for the future".
The Trust said it had campaigned for Chainrai to leave the club and return it to the fans, saying it hoped Wednesday's developments "could be the light at the end of the tunnel".
"Portsmouth FC is the lifeblood of the fans and the city, and we ask all supporters of the club, the people of Portsmouth and football as a whole to support the work of the Pompey Supporters Trust in their continued efforts to secure its future," a statement said.
"SOS Pompey intend to hold a peaceful demonstration of our pride in our manager and players before this Saturday's game against Bournemouth at the gates of Fratton Park at 2.15pm, and we ask all fans to join us in showing how much we appreciate the work of the manager and staff of our magnificent club."
On Friday, it had seemed Portsmouth had evaded closure when Liam Lawrence, the last senior player remaining on the Fratton Park books, agreed to leave.
Birch had set a deadline of August 10 for every senior player to be off the wage bill, saying he would otherwise be forced to shut Portsmouth down.
"We have negotiated a compromise agreement with Liam Lawrence, who will leave the club when the paperwork is finalised,'' a statement from Birch on the club's official website read.
"I'd like to thank Liam for his support, and all of the other players, for putting the club's interest ahead of their own. They have all had to make very difficult decisions and been placed in an impossible position which wasn't of their making.''
On Thursday, Portsmouth reached a deal with defender Tal Ben Haim, who agreed to leave. That meant only the cases of Lawrence and forward Kanu then remained to be resolved.
In a statement, Birch said: "The progress we have made over the past 24 hours means there is now a much better prospect of completing the sale of the club and avoiding liquidation."