Gary Megson and Alan Curbishley have emerged as the early favourites to replace the sacked Phil Brown as Hull manager.
Brown was "relieved of his duties" and placed on gardening leave by the Tigers this morning.
Chairman Adam Pearson cited the club's perilous position in the Barclays Premier League as the reason for the surprise decision.
Former Charlton boss Curbishley has been out of work since leaving West Ham in September 2008 while Megson is available after being dismissed by Bolton in December - coincidentally after a draw with Hull, who recovered from 2-0 down in the second half.
Paul Jewell and Steve Coppell have also been linked while Brown's assistant Brian Horton, himself a former Tigers boss, could be a contender.
Horton and fellow coach Steve Parkin have been placed in temporary charge of the team "until further notice", and Brown has spoken of his sadness at the sudden decision to dispense with his services.
The 50-year-old is the most successful manager in the club's history, having led them to the top flight for the first time in 2008 and then kept them there last year.
"I am obviously very disappointed with the club's decision and the fact that I will now not have the opportunity to secure Hull City's status in the Barclays Premier League for a third consecutive season," said Brown in a statement released through the League Managers Association.
"Although I am extremely sad to be leaving Hull City, I am very proud of my achievements during my time as manager, especially having led the team into the top flight of football for the first time in the club's 104-year history and ahead of schedule."
Brown leaves the Tigers 19th in the table and three points adrift of safety following a last-gasp loss to Arsenal on Saturday.
Hull have won just five games all season, none of them away from the KC Stadium, and lost on their last four outings.
Pearson claims taking such decisive action at this late stage of the season - with just nine games remaining - was in the best interests of the club.
A statement from Pearson read: "Retention of Premier League status is paramount and the board believes that a change in managerial direction is the correct option at this time."
Pearson, who returned to the club for a second spell as chairman last October, has repeatedly warned of the dire financial consequences of relegation.
Hull, under previous chairman Paul Duffen, overspent on player wages in the aftermath of their promotion to the Premier League.
Efforts were made to offload fringe players in the January transfer window but the club, £9million in debt, were unable to make major savings on their wage bill.
It is feared a player cull will be necessary if the Tigers fail to preserve their top-flight status.
Former Hull manager Peter Taylor, who won promotion to the Championship with the club, believes fear of such drastic measures may have hastened Brown's demise.
Taylor told Sky Sports News: "Because of the financial situation, if they go down it'll be very, very serious for the club.
"So maybe it's just the last throw of the dice.
"It doesn't mean Phil's a bad manager and it doesn't mean whoever takes over is a great manager.
"It's just sometimes a change of face all of a sudden lifts the club."
Nevertheless, the decision to part company with Brown still came out of the blue.
Brown was thought to be one game away from the sack at the time of Pearson's return following a poor start to the season but he appeared to have weathered the storm.
A dramatic win over Stoke on November 8 sparked a mini-revival and performances since, if not results, suggested the manager had not lost the dressing room.
Brown, however, did have to apologise last week after members of the Women's Institute witnessed a public bust-up between team-mates Nick Barmby and Jimmy Bullard during a training exercise close to the Humber Bridge.
Duffen, a strong supporter of Brown during his time at the helm, believes Hull may already have a successor lined up.
"These things rarely happen as knee-jerk decisions," Duffen said.
"Some of the bookies slashed the odds last week for Phil to be sacked and I'm sure there will have been conversations and movements going on in the background long before today.
"I would be surprised if there isn't a new manager already pencilled in."
Hull was Brown's second managerial assignment after failing during a previous spell at Derby.
The former Bolton assistant boss was appointed in January 2007 having worked as assistant to his predecessor Phil Parkinson.
He saved the club from relegation from the Championship that year and then gloriously led them to promotion via the play-offs 12 months later.
Hull then made a remarkable start to life in the Premier League, taking 20 points from their first nine games, but form deserted them and they only survived relegation on the final day of the season.
This term has been a struggle and Brown, despite taking points off Chelsea and Manchester City last month, has now paid the price.