Walter Smith is urging Rangers fans to support boardroom changes after he stepped down as chairman at Ibrox.
The former manager referred to a “highly-dysfunctional environment” at board level.
And he wants the general meeting of shareholders that was requested last week to take place soon.
Smith said: “I am now imploring everyone to back these proposed changes so that much-needed stability and a level of integrity can be restored.”
The 65-year-old also called for his successor Ally McCoist to be given the chance to manage the club “under conditions similar to those which were afforded his predecessors”.
A group thought to be led by Scottish businessman Jim McColl is seeking to wrest control from the regime currently fronted by chief executive Craig Mather.
With a power struggle in full swing, Smith is backing calls for former director Paul Murray and Frank Blin to join the board, although he stated that Mather was doing a good job and hoped he would be able to continue.
“As a manager I had to make many difficult decisions but none was tougher than the one I have just made”
Smith had been involved in failed takeover attempt with McColl shortly after Charles Green’s consortium had purchased the liquidation-bound club’s assets and business last June.
Green subsequently invited Smith to join the board and he took up the non-executive post of chairman at the end of May.
But the ex-Scotland boss did not last long in the position, saying that his resignation was “the only option left open”.
Green, who quit as chief executive in April, is returning in a consultant’s capacity and immediately angered McCoist by warning the manager he would need to win a cup.
And Smith has a great deal of sympathy for his former assistant, saying: “As for Alistair McCoist, it is important that we all appreciate that no other Rangers manager has had to work with poorer or more trying circumstances.”
Smith, who won 21 major trophies in his two spells as Rangers manager, then turned his focus to the fans, whose main representative groups issued a joint statement expressing “deep anxiety” over his departure.
“They have suffered agonies and tortures over the last two years but they can be proud of their contribution,” he said.
“They did not waver in their support of their club and as far as I am concerned they have been absolutely the one outstanding feature of this club.
“Indeed, they are a reminder to those in the boardroom that directors have the massive and ultimate responsibility of serving, protecting and nourishing this club for the benefit of the fans and not an individual or any associates.
“As a manager I had to make many difficult decisions but none was tougher than the one I have just made.
“Stepping away from this club is heart breaking but I will always be grateful for the support Rangers fans have given me down through the years.”
The group of shareholders calling for change are believed to hold approximately 30% of shares in Rangers but hope to persuade enough institutional shareholders and supporters to get a majority.
Rangers had 21 days to respond to the requisition and would have another 21 days to constitute an extraordinary general meeting to vote on the request if they deem it viable.
Mather, who expressed sadness at Smith’s decision to resign, has labelled the challenge “ill-considered and ill-timed”, saying: “We will not be defeated, I certainly won’t.”