From the high of winning the FA Cup two years ago, the club have spiraled down into a chaotic black hole of debt and misadministration that has left fans angry and bewildered and financial observers bemused.
However, the administrators called in to stabilize the club and try to clear debts of some 70 million pounds ($106.6 million) said that they were confident Portsmouth would survive and would be playing football next season.
If they do, it will almost certainly be in the Championship (second division) as the decision to go into administration should incur an automatic nine-point deduction. With the club already seven points adrift, relegation appears unavoidable.
Portsmouth, founded 112 years ago, had been due in the High Court next week to face a winding-up petition from the British government's Revenue and Customs department over tax debts.
In a hearing earlier this month, they had been given time to secure new funding or a new owner but they failed on both fronts and instead became the first Premier League club to go into administration.
The south-coast club, who have raised almost 100 million pounds ($153.4 million) in player sales in the last 20 months, issued a statement on their website (www.portsmouthfc.co.uk) confirming that they went into administration at 1020 GMT.
Chief executive Peter Storrie announced that, once the administrators had found a new owner, their fifth in a year, he would stand down.
Administrator Andrew Andronikou, of insolvency experts UHY Hacker Young, has already set about his duties.
"It is imperative that if this club is going to survive it functions within its means by avoiding trading at a loss," Andronikou told a televised news conference at the club's Fratton Park ground.
"We are fortunate to have inherited a list of interested parties and will explore the list with a view to finding an investor or outright purchase." Andronikou said he hoped Portsmouth would be given special dispensation to sell players outside the transfer window and that the Premier League would consider advancing their "parachute payment" of around 16 million pounds.
"I need to generate working capital and we will have to sell one or two players and that's the reason we are to talking to the Premier League to look for a concession," he said.
"To the supporters I promise you we will save your club and take it forward. From what I have seen I have every confidence that Portsmouth will be playing football next season." He added that manager Avram Grant would stay with the club until the end of the season.
Storrie, however, will not, having announced his intention to resign in a statement on the website.
"Whilst accepting as chief executive that it was inevitable that criticism would come my way, the overall funding of the business was the responsibility of the owner," Storrie said.
"What I am not prepared to accept is the very personal level of abuse on websites, emails and local radio which I have received over the last couple of days." The club's players, who have had their salary payments delayed several times this season, trained as normal on Friday ahead of Saturday's league game at Burnley.
Earlier on Friday, another south-coast club, League Two (fourth division) promotion candidates Bournemouth, were issued with a High Court winding-up order after they too failed to pay a Customs and Revenue debt while former League club Chester City were expelled from the Football Conference for debt-related problems.
