Rangers' administrators may not name a preferred bidder for the Ibrox club on Monday despite previously expecting to do so.
Duff and Phelps said on Friday that they would look to proceed with USA businessman Bill Miller's £11.2million bid on Monday if no other offers were forthcoming.
However, the Blue Knights consortium, led by former Ibrox director Paul Murray, are back in talks over submitting a fresh proposal and, in broad terms, both bidders have asked for more time to look at issues such as funding and potential sanctions.
The Blue Knights were in line to become preferred bidders more than a week ago but could not immediately pay the £500,000 exclusivity fee and then stepped back after discovering potential partners Ticketus were negotiating with Bill Ng's Singapore group, who have since withdrawn.
Ticketus, the London-based investment firm whose money helped Craig Whyte buy Rangers from Sir David Murray last May, are owed £26.7million by the club but they, like Whyte, have been ignored by Miller.
The towing tycoon's plans involve transferring assets to a new company and trying to achieve a CVA (company voluntary agreement) with the existing company.
However, there remain huge questions over his bid given it is dependent on receiving written assurances from the football authorities that a new Rangers would not be punished next season.
The Scottish Premier League clubs are due to vote on April 30th on proposals that would see 'newco' clubs deducted money and points for several seasons.
Meanwhile, Ticketus remain confident they will be recompensed whichever way Duff and Phelps proceed with the proposed takeover.
A spokesman for the company said: "We have been negotiating with the Blue Knights over the weekend and talks are at a detailed stage.
"I think it has been rhetoric from Bill Miller. For one thing, how is he going to get Craig Whyte's shares?
"In the worst-case scenario, Ticketus become a creditor in a CVA.
"We wouldn't get all the money back but, whatever happens, Ticketus have protection, we have the ability to address any shortfall by going after Craig Whyte for the rest of the money.
"We want to be helpful but we are not doing a deal that is wrong for Ticketus."