Virginia Slims Circuit

The Virginia Slims Circuit was a tennis tour consisting of a group of originally nine female professional players. Formed in 1970, the Virginia Slims Circuit eventually became the basis for the later named WTA Tour. The players, dubbed the Original 9, rebelled against the United States Lawn Tennis Association (USLTA) due to the wide inequality between the amount of prize money paid to male tennis players and to female tennis players.

The Open era began with the British Hard Court Championships in Bournemouth in 1968. At the first Open Wimbledon, the prize-fund difference was 2.5:1 in favour of men. Billie Jean King won £750 for taking the title, while Rod Laver took £2,000. The total purses of the competitions were £14,800 for men and £5,680 for women. By the 1970s, the pay difference which had been a 2.5:1 ratio between men and women had increased. In 1969, ratios of 5:1 in terms of pay were common at smaller tournaments; by 1970, these figures increased to 8:1 and even 12:1.

The situation came to a head in 1970, when most tournaments offered four times as much prize money to men than they did to women. At the 1970 Italian Open, men's singles champion Ilie Năstase was paid US$3,500 while women's singles champion King received just US$600. On top of this, the USLTA failed to organise any tournaments for women in 1970.

King and eight other female tennis players - Americans Rosemary Casals, Nancy Richey, Peaches Bartkowicz, Kristy Pigeon, Valerie Ziegenfuss, and Julie Heldman and Australians Kerry Melville Reid and Judy Tegart Dalton - decided to enlist World Tennis magazine publisher Gladys Heldman to help negotiate for greater equality in prize money and provide valuable public relations assistance. All the players were putting their tennis careers at risk because the influential USLTA did not back them.

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