A number of bookmakers yesterday suspended betting on Brown being the next Premier League manager to leave his job.
The Tigers responded to the ensuing speculation in a statement last night to deny Brown's position was under review, but uncertainty remained with reports that former chairman Adam Pearson was set to make a shock return to the club.
Allies: Former Hull chairman Paul Duffen (left) and Phil Brown (right)
Pearson last night resigned from his post as chairman of football at Derby, heightening speculation he is set to replace Duffen, a close friend of Brown, at the KC Stadium.
A club statement confirmed Duffen's departure: 'The club has received a letter of resignation from Paul Duffen, executive chairman of Hull City AFC and Superstadium Management Company Ltd, which has been accepted and is effective immediately.'
Brown insisted yesterday that he remains the right man for the job and intends to remain in his post for a number of years to come, and he arrived at the Tigers' Cottingham training ground at around 9am today bidding to put the uncertainty to one side.
Former Hull striker Dean Windass has called for Brown to be "moved on", with the club having managed just eight points from their opening 10 games of the season.
Outspoken: Former Hull striker Dean Windass has called for Brown to leave
Windass, who left Hull in January, told talkSPORT magazine: 'Phil's done a fantastic job since he's been there but I think it's time that he should get moved on and bring somebody else in.'
Windass also questioned whether the club could stay up this season, adding: 'It's going to be difficult. They're not getting results and they're struggling to score goals at the moment.
'They need a 10-15 goal-a-year striker to get away from the bottom of the table. They've got a little mini-league at the moment and it's important they win games against teams in and around their league.'
Hull sought to play down the speculation surrounding Brown's position in a brief statement last night, which read: 'Contrary to media speculation the club can confirm that Phil Brown has not been sacked and remains the manager of Hull City Football Club.'
Uncertain future: Jan Vennegoor of Hesselink (left) and Bernard Mendy (right), in action against Portsmouth, are at a club with long-term financial doubts
However, the future of the Tigers is set to remain in the spotlight after concerns also surfaced about the club's long-term financial position, stemming from accounts being published covering the year ending July 2008.
In that 12 months Hull made a loss of nearly £10million as they won promotion to the Premier League via Windass' goal in the 2008 play-off at Wembley.
That sum, however, did not include any figures from the club's first season in the top tier of English football, and the directors remained confident the next set of results will prove more positive.
Duffen took over at the KC Stadium from Adam Pearson in 2007 and oversaw the club's rise to the top flight for the first time in their history, which was achieved via victory in the 2008 Coca-Cola Championship play-off final.
Pearson yesterday resigned as chairman of football as Coca-Cola Championship club Derby County, sparking suggestions he is set to return to East Yorkshire.
Poor start: Hull have taken just eight points so far this season, which has included a 6-1 thrashing against Liverpool and a rampant Fernando Torres (right)
Hull avoided relegation on the final day of last season but chairman Duffen and manager Brown both came under pressure following their poor start to this campaign, which has seen them take just eight points from their opening 10 games.
The Tigers' statement continued: 'The club wishes to express its gratitude to Paul for his outstanding contribution as chairman during a period of unprecedented success for Hull City AFC.'
The club will reveal more on their future plans next week, with the statement concluding: 'The recruitment process has commenced in respect of the appointment of a new executive chairman and a further statement in relation to this will be issued by the club on Monday 2nd November."
Duffen issued his own statement, which read: 'When I succeeded Adam Pearson as chairman of Hull City Football Clubin June 2007 I was very aware of the responsibility to build on hislegacy.
Rocking the boat: Jozy Altidore (centre) caused upset at Hull last week with his Twitter comments after being dropped for arriving late for a match
'I articulated an intention to take the Tigers to the previously uncharted waters of the Premier League and to the eternal credit of the players and coaching staff, that seemingly ridiculous ambition was achieved 11 months later thanks to a victorious debut appearance at Wembley in the play-off final.
'The start to our maiden top-flight campaign broke all previous records for a newly promoted side and ensured that 2008 will forever be remembered as the most remarkable year in Hull City's history.
'Football is a results business and in the same way that I enjoyed the successes of the previous two seasons, so I must take ultimate responsibility for the disappointments of 2009.
'It has been a tremendous privilege to lead the Tigers on this amazing journey and I pay tribute to all the staff for their hard work and dedication as well as to the fans for their magnificent support. I am proud to have played my part and wish the club every success in the future.'
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