Rangers owner David Murray may sell the club within the next three years and has already been approached by potential buyers.
Murray took control of Rangers in 1989
The 54-year-old entrepreneur bought Rangers for £6m in 1989.
And he told the Financial Times: "I'm coming up for 20 years, and I think that will be enough for anybody.
"We've had a couple of people speak to us tentatively, but I would only sell the club if it was somebody who could take it to a higher level."
Murray's portfolio of metals, mining, property and venture capital businesses have made him Scotland's fifth richest man, worth £650m.
His investment at Rangers helped secure a famous nine-in-a-row championship wins between 1989-1997.
And the club's £12m training facility, Murray Park, is named after him.
Murray stepped down as chairman at Ibrox in July 2002 but returned to the post in the summer of 2004.
John Macmillan, secretary of the Rangers Supporters Association, said: "I am confident Mr Murray would only sell to someone with the best interests of the club, its players and supporters at heart.
"It's true he has had his detractors who say he only took over Rangers for his own profile but he has invested lots of time and his own money in the club."
Stephen Smith, of the Rangers Supporters Trust, added: "Our biggest nightmare would be a Malcolm Glazer taking control at Ibrox.
"One man who might be interested is Sir Tom Hunter, he's known to be a big Rangers fan. But we don't want one unaccountable rich man replaced with another.
"David Murray owns 91.8% of the club, that's unhealthy, and whoever takes over we would like to see ownership radically overhauled and re-distributed."