Billie Jean King was in no mood for indecision.
"I got everyone in the room and told Betty Stove to lock the door. I said: 'Don't let anybody out because I can't spend one more ounce of my life on this. If we can't make this happen today, I'm finished.'"
Forty years ago on 20th June 1973, King and more than 60 of her fellow female players broke off from their Wimbledon preparations and congregated at London's Gloucester Hotel.
With the nearly 6ft Stove guarding the door, there followed a discussion that would change sport forever. King had already asked her then-husband Larry to draw up contracts rubber-stamping the formation of the Women's Tennis Association.
After much discussion and debate, the players eventually emerged holding the signed contracts. The WTA was official, and King was its first president.
"We just wanted a situation where any player in the world, if she was good enough, would have a place to play and make a living and be recognised and appreciated," King said recently in an interview.
By the time of the Gloucester Hotel meeting, three years had already passed since King and eight other players (the so-called 'Original 9') signed symbolic $1 contracts to compete on the Virginia Slims circuit, formed in direct response to the vast inequalities in prize money between men and women.
In King, female players had the perfect figurehead: a hugely respected champion (she won 12 major singles crowns and 39 Grand Slam titles in all) and an expert politician who made the case for equality in firm but reasoned tones.
Later in 1973, she would take on - and beat - Bobby Riggs in the infamous 'Battle of the Sexes' - which remains the most-watched tennis match of all time with an estimated television audience of 100 million. It is the subject of a new documentary, released to coincide with the 40-year anniversary.
"It wasn't about a tennis match," King has insisted. "It was about social change."
Global superstars like Serena Williams and Maria Sharapova would testify that King's mission was a success.
"If we hadn't had Billie, our sport wouldn't be where it is today," says current WTA chief executive Stacey Allaster. "She is as active today in the WTA as she was in 1973."
King will join the rest of the 'Original 9' as well as a host of past and present superstars of the women's game at Wimbledon on the middle Sunday to celebrate 40 years of the WTA.
As Allaster notes, the 69-year-old King remains as influential today as she was back in 1973.
“Billie Jean fought a lot for us on and off the court: for getting equal prize money, for equal rights for the understanding of what we do, how powerful it is and how inspiring it is to women around the world," former world No.1 Sharapova told London's Evening Standard newspaper.
"She kept in touch with me when I was out of the game for 10 months injured. She texted me a lot and still does, no matter if I win or lose matches she keeps in touch."