Jim McColl has revealed he is not looking to lead a Rangers takeover.
But the wealthy Scottish businessman confirmed he was putting his weight behind calls for boardroom change in his capacity as a Rangers shareholder.
Engineering tycoon McColl, whose personal wealth was estimated at £1billion in last year's Sunday Times Rich List, backed outgoing chairman Walter Smith's calls for fans to get behind formal moves to install Paul Murray and Frank Blin on to the board.
In a statement, the Clyde Blowers chairman and chief executive said: "Let me make it very clear, I am not seeking to join the board or to increase my shareholding in the club.
"I am a small shareholder like many of the club's fans and have no intention of increasing my position in the short to medium term.
"I am 100 per cent focused on my own businesses and the strategy which I have agreed with the investors in my funds. I am duty bound to honour that agreement.
"This is not because I don't believe investing in Rangers would be a good investment, it is because of the commitment I have made to my own businesses and to my partners.
"On the contrary, I believe that with a strong reconstructed, effective and highly competent board to restore financial transparency, stability and success to the club, it is a very attractive investment opportunity.
"This requisition for change is not about any one person or group of people trying to gain a controlling position, this is a demand for change by some very concerned investors, fans and other stakeholders.
"Things have to change to allow the club to move forward with ambition and confidence.
"The board needs to be constructed to reflect balance, independence and experience to operate in the best long-term interests of the club, fans and shareholders rather than the interests of a small clique."
McColl was involved in an unsuccessful bid to buy Rangers from Green's consortium immediately after it bought the liquidation-bound club's assets and business for £5.5million in June last year.
But his involvement now is as a member of a group of disgruntled shareholders, albeit an influential one, who last week called for former PricewaterhouseCoopers Scotland executive chairman Blin and former oldco Rangers director Murray to join the board.
The group wants Craig Mather to be removed along with Bryan Smart and Brian Stockbridge, both of whom are associates of Charles Green, and have demanded an extraordinary general meeting, a request the board is considering.
McColl said: "I would support Walter's call and urge the board to do the right thing and accept the changes proposed in the requisition recently received from a group of concerned investors.
"Acceptance will avoid the unnecessary expense, disruption and delay of a general meeting.
"This is an important step towards building a strong, effective, highly competent board to restore financial transparency, stability and success to the club."
Smith's decision to quit came three days after the club announced the return of Green as a consultant. Green is back less than four months after he resigned as chief executive amid an investigation into his links with former Rangers owner Craig Whyte. And McColl hopes the former Rangers boss can be restored to the board at some stage.
McColl said: "Walter as chairman should have been given the position he has rightly earned to be an ambassador for the club, to offer wise counsel in the many facets of the club's operations, ranging from representing the club; helping set the club's tone and standards; working with the communities we serve; liaising with the fan base and helping the club rebuild its reputation with the football regulators."
Smith argued Mather should be allowed to continue as chief executive but McColl believes he should step down from the board and "remain as a candidate for the role alongside external candidates as part of a formal selection process".
McColl added: "The board should undertake a proper search to identify the best candidate for the job."