Equal opportunity laws in the U.S. were still two years away when Billie Jean King barricaded 63 of her colleagues in a room at the Gloucester Hotel in central London and emerged triumphantly waving legal papers that led to the formation of the Women’s Tennis Association (WTA) 40 years ago.

The WTA has announced plans for more than 20 of the 23 women who have since been ranked number one to gather at a glitzy event on the middle weekend of Wimbledon, which begins on Monday, to commemorate what became not only a seminal sporting moment but a key staging post in the battle for equality.

“What started as a few women and a dollar has grown to thousands, living the dream — our dream. We were athletes who wanted to compete — and along the way we made history, determined to win, not just for ourselves, but for women everywhere”, says Ms. King in a WTA campaign to mark the milestone.

Against a febrile backdrop in the summer of 1973 Ms. King, who won the fifth of her six Wimbledon singles titles that year, called a meeting of her fellow players amid widespread and intense frustration at sexism and inequality in the sport.

Particularly angered by a tournament in Los Angeles where the women’s champion earned a sixth of the prize money of the men, Ms. King became in 1970 one of a group of players — The Original Nine — who each signed nominal $1 contracts with World Tennis publisher Gladys Heldman to compete in a newly created Virginia Slims Series.

Three years later in London she got everyone in the room, told fellow player Betty Stove to lock the door and emerged clutching legal documents that were drawn up by Larry King, the tennis player’s then husband.

“If we hadn’t had Billie, our sport wouldn’t be where it is today. She was the catalyst, the dreamer, the person who said ‘we will do this and we will be successful’. She is as active today in the WTA as she was in 1973”, said Stacey Allaster, the WTA chief executive, recalling how the pioneering players of the 1970s would have to drum up publicity for their own tournaments in small towns across America.

Later in 1973, Ms. King would beat Bobby Riggs in an exhibition match in the US dubbed “the battle of the sexes”.

Ms. King, the daughter of a fire-fighter from Long Beach, made her Grand Slam debut aged 15 in 1959 and two years later neighbours raised $2,000 so she could play at Wimbledon. There she won the women’s doubles at her first attempt, the first of 39 Grand Slam titles that included 12 singles triumphs. She retired from competitive singles in 1983 having seen the sport transformed.

Amid a passionate debate about the amount of coverage and profile afforded women’s sport, most recently reanimated here following London 2012, tennis is one of only a handful of sports in which women can genuinely claim equality of opportunity and potential financial reward.

Prior to the formation of the WTA in 1973, the annual prize money available to professional female tennis players was around $2 million. Today it is $118 million across the WTA’s 54 tournaments in 33 countries and the four Grand Slams.

Those original nine players will be present alongside most of the number ones of the past 40 years, from Ms. King to Serena Williams.

“I was lucky enough to meet the original nine last year [2012] in Charleston. It’s thanks to Billie Jean King that we have everything in professional sport that we have today. It’s amazing”, said Martina Hingis, who has won five Grand Slams and will also be present.

Ms. Allaster said that without King and her colleagues, the riches and opportunities on offer today would not exist. “They set the course. Today’s players know the debt they owe Billie and the original nine and all the generations that have come before them to make tennis the number one sport in the world for women”, she said.

But although there is now equality of prize money at the four Grand Slams, which took until 2007 at Wimbledon, there are other tournaments where there is still a big gap, said Ms. Hingis.

“It’s 2013. But the men still generally make a lot more. At least there’s equality at the Grand Slams but at all the other tournaments, there’s still a gap.” Ms. King passed the baton of WTA president to Chris Evert, whose rivalry with Martina Navratilova took women’s tennis to new heights.

Ms. Evert said the women’s game “started as a small intimate family and evolved into a big business”.

“It started with one sponsor in Virginia Slims and turned into hundreds of sponsors vying for a position in sponsorships,” she said. “The prize money, exposure, the fan base, sponsorships, media and even the level of tennis greatly improved. Also the tour became more international.” The women’s game has come under fire in recent years for, variously, not producing enough characters and dominant players to rival a golden period for the men’s game or, conversely, becoming too predictable and dull.

Ms. Allaster argues that the balance is now about right, with a host of young players from around the world coming through to challenge the leading players including Serena Williams, Maria Sharapova, Victoria Azarenka and Agnieszka Radwanska.

Ms. Radwanska, the Pole who reached the Wimbledon final last year, said the women’s tour was getting “better and better every year”.

“We can see that a lot of things have changed in the last 10 or 20 years. I think it’s great. I think we can really see that the women’s game is bigger than before. We can see more matches on TV and people are more interested in women’s tennis”, she said.

For Ms. Evert, Ms. King’s hotel room revolution blew open the doors for those who followed, enabling a professional tennis career that provided “the opportunity for a woman to compete at the highest level, to be proud of her physical and mental strength and to take advantage of the opportunity to be a positive role model”.

© Guardian News Service

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