As Wimbledon gets under way, former U.S. tennis champion Billie Jean King is telling the tale of how she struck one of the most famous blows for female equality in a new documentary film.
"The Battle of the Sexes" recounts King's journey from an amateur player to a feminist sports idol whose 1973 defeat of self-confessed "chauvinist pig" Bobby Riggs set women's rights and tennis on the road to a modern game where Serena Williams can enjoy equal status and prize money with Novak Djokovic.
At the film's premiere in the Scottish capital this weekend, the 69-year old six time Wimbledon champion told Reuters that these days, top players like Williams have come a long way from 1970s, when the documentary says women needed approval from their husbands to arrange their own finances.
"Well, I would say for the most part the players today are living our dream," said King, who narrates and is executive producer of the film directed by James Erskine and Zara Hayes.
The year she beat Riggs, King also won Wimbledon to earn 3,000 pounds. The 1973 men's champion, Jan Kodes, earned 5,000 pounds. This year the men's and ladies' singles champions will each take home 1.6 million pounds ($2.46 million).
The film's historical footage follows King's rise as a young tennis prodigy alongside the bra-burning demonstrations of the U.S. women's movement cut with contemporary TV commercials in which men order their wives to iron their shirts and rail against the stroppy proponents of feminism.
As King matures, joins the breakaway pioneers of a professional women's tennis circuit and then founds the Women's Tennis Association (WTA) to fight for better recognition, along comes the ageing, fast-talking, hustler and retired Wimbledon champion Bobby Riggs with a challenge.
The brash and compulsive gambler - who died in 1995 - said the female game was inferior and that even at the age of 55, a top female player could not beat him.
Women's tennis "stinks" he says.
He badgers King for a match. He lampoons feminism at every photo opportunity. But when he persuades the much-decorated Australian champion Margaret Court to play him and then beats her handily in a packed stadium. The die is cast.
"I knew I had to play him then," King recalls in the film, setting the stage for the $100,000 winner takes all match.
The film climaxes with the nail-biting on-court confrontation between the 29-year-old queen of the court and self-promoting Riggs in Houston, Texas that was watched by some 100 million people on television.
"Billie Jean King is one of the all-time tennis greats, she's one of the superstars, she's ready for the big one, but she doesn't stand a chance against me, women's tennis is so far beneath men's tennis," Riggs said before the match.
But the standard bearer for equal rights, and the political poster girl for the women's liberation movement had his number.
"He's a hustler off the court. I'm a hustler on the court and that's where it matters," King tells a pre-match interview.
The outcome is well known. King beat Riggs in straight sets.
But in a film generously sprinkled with a contemporary soundtrack featuring hits from Aretha Franklin, John Lennon, Diana Ross And The Supremes and Helen Reddy, King recounts another battle she was also fighting and has carried on since.
Although married from a young age, King had realised by 1973 that she was gay and feared that if the media discovered her sexual orientation it would set back her efforts for the women's movement for years.
But that struggle has also come a long way in the four decades since she beat Riggs and in 2009 she was one of 16 recipients of the U.S. Medal of Freedom, the nation's highest civilian honour for services to the country.
Given the award for being an "agent of change", the White House praised King for helping to champion gender equality issues not only in sports, but in all areas of public life and hailed her as one of the first openly lesbian major sports figures in America when she came out in 1981.
"It was very nice to be honoured, and also for the LGBT (Lesbian, Gay, Bisexual, Transgender) community," King told Reuters. "Obama was actually the first president who said the word LGBT."
King's Edinburgh visit followed a 40th anniversary reunion in London's Gloucester Hotel where 40 of the world's top women players, inspired by King, formed the WTA at a secret meeting.
"When I have a general meeting with the WTA, they have me come in and speak," she said.
"(I say) I'm so happy you guys are living the dream, our dream that we had for you, it's actually happening, but we are like a symbol for the way the world looks, we're a good message."