BOB Murray has urged Sunderland's fans not to hamper the club's development by refusing to renew their season tickets until Niall Quinn's proposed takeover is complete.

Quinn's consortium, which is being backed by leading Irish property developers Sean Mulryne and Sean Dunne, is currently undergoing a process of due diligence ahead of a formal offer for Murray's 56.8 per cent stake in the Black Cats.

But with the group's examination of Sunderland's books taking longer than expected, a formal approach is still around a fortnight away.

Once an offer is made, it will trigger a 'Rule 9' approach to all shareholders, who would then have 21 days to respond to Quinn's bid.

That would mean the Irishman not taking formal control of the Black Cats until the start of July at the earliest.

With a large number of the club's fans having lost faith in both Murray and the current playing squad, a sizeable number are refusing to renew their season tickets until takeover talks are complete.

Earlier this week, a survey by Virgin Money suggested that 26 per cent of Black Cats fans consulted would not be renewing their tickets.

Murray claims he understands the fans' frustration after a season that has entered the record books as the worst in Premiership history.

But the outgoing chairman has called on supporters to come to the club's rescue in its hour of need.

The longer the fans put off renewing their season tickets, the less funds will be available to the new consortium for squad strengthening ahead of the new Championship campaign.

And, while Murray cannot be accountable for his successors' actions, he insists they will be in a stronger position if the bulk of the club's season ticket holders have affirmed their commitment.

"You will be aware, I am sure, that the board of Sunderland Limited recently announced that it is in discussions with former Sunderland and Republic of Ireland striker Niall Quinn and a consortium of private investors regarding their ambitions to potentially acquire control of Sunderland AFC," he said in a letter that was delivered to season ticket holders yesterday.

"While these discussions continue in the coming weeks, the club must continue its normal commercial activities, and this means we cannot wait for the outcome of this process before commencing season ticket renewals for the new season.

"I appreciate that your loyalty has been severely tested in recent months and I am truly sorry that you have been let down in this way.

"I share your frustration with the last season. I have taken my share of criticism and I acknowledge that.

"But in this time of potential change for the club and all supporters, the only way to secure your seat and your rightful place in its future is to renew your season ticket.

"We have decided that prices for next season will be rolled back to the season ticket prices of 2004-05 when we won the Championship.

"In this way, the club would like to thank you for your continued support and ensure you do not lose out financially during any potential transition period."

Meanwhile, Sunderland have tied teenage goalkeeper Trevor Carson to a new one-year deal in an attempt to negate the impact caused by the possible loss of Ben Alnwick.

Carson is one of only two members of last season's Academy team - along with centre-half Peter Hartley - to have secured a professional deal.

Alnwick, who is contracted to the Stadium of Light until 2008, has submitted a formal transfer request after making just five Premiership starts last season.

Tottenham boss Martin Jol has monitored the 19-year-old's development and is expected to make a £500,000 bid for his services before the end of the month.

Given the club's current state of flux, it is difficult to see how the Black Cats can prevent one of England's most highly-rated young goalkeepers becoming Paul Robinson's deputy at White Hart Lane.

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