In this April 7, 2012, file photo, members of the original nine women, from left to right, Billie Jean King, Peaches Bartkowicz, Kristy Pigeon, Valerie Ziegenfuss, Judy Tegart Dalton, Julie Heldman, Kerry Melville Reid, Nancy Richey and Rosie Casals, who helped start the women’s professional tennis tour are honored at the Family Circle Cup tennis tournament in Charleston, S.C. The nine signed a dollar contract 50 years ago, and it turned into millions for female tennis players. They were tired of being squeezed out of events by promoters and paid 10 times less than men. (AP Photo/Mic Smith, File)

NEW YORK (AP) — Serena Williams could send a thank-you note to Billie Jean King and eight other players who signed $1 contracts to launch a new women’s pro tennis circuit 50 years ago.

The bold move by King and her peers, known as the “Original 9,” led to the lucrative prize funds and multimillion-dollar endorsement deals enjoyed by top women today.

They were tired of second-class treatment at tournaments. They’d been squeezed out of events by promoters and were paid substantially less than men.

So the Original 9 broke with the tennis establishment and joined promoter Gladys Heldman to form the Virginia Slims circuit. They signed $1 contracts with Heldman on Sept. 23, 1970, despite a threat from the U.S. Lawn Tennis Association to ban them from Grand Slam tournaments or from representing their country at international events.

“We risked our careers,” King said in an interview with The Associated Press. “Even if we didn’t play again after the tournament, we didn’t care because something had to be done.”

Heldman enlisted longtime friend Joe Cullman, the CEO of tobacco company Philip Morris, to sponsor the upstart circuit. King and the women held up their dollar bills with joy and trepidation that day, ahead of the inaugural Virginia Slims Invitational in Houston.

The Original 9 included seven Americans — Heldman’s daughter, Julie, along with King, Rosie Casals, Peaches Bartkowicz, Kristy Pigeon, Nancy Richey and Valerie Ziegenfuss — and two Australians, Judy Tegart Dalton and Kerry Melville Reid.

Their tenacity and vision led to the creation of the Women’s Tennis Association in 1973 as the organizing body for women’s pro tennis. The WTA Tour now offers 55 events in 29 countries and $179 million in total prize money.

The WTA and U.S. Tennis Association will celebrate the 50th anniversary of the founders’ achievement during the U.S. Open. All four Grand Slam tournaments now pay women the same prize money as men after years of advocacy by King for equal pay. The women’s and men’s champions at this year’s U.S. Open will each receive $3 million.

“Sometimes you need someone, or a group of women, strong people, to stand up,” Williams said Saturday after she won her third-round U.S. Open match. “They were standing up for the future generations, and that takes a lot of humility and a lot of courage. I’m greatly appreciative.”

OPEN AND SHUT

The Open Era began in 1968, allowing all players to be paid professionals, and King talked to male players about forming a tennis association. Men and women played together at the Grand Slam events and some other tournaments.

King and her then-husband, Larry, had met while playing tennis at Cal State Los Angeles in 1963. He became a tennis promoter and saw a dismal future for women’s tennis, with more tournaments, money and TV exposure for the men.

“Larry already told me, when tennis went open, that the men would try to get rid of us,” she said. “I said, ‘No they won’t, they’re my friends.’ He said, ‘Billie, they own the boys network, it will be gone.’”

By 1970, the 26-year-old King realized Larry was right. The breaking point came that summer, when the Pacific Southwest Open in Los Angeles, chaired by former player and influential promoter Jack Kramer, announced the men’s champion would get $12,500 and the women’s winner $1,500.

That galvanized the nine women to launch their own tour. Julie Heldman said the upstart group benefited from the “holy trinity” of tennis — her mother’s connections as publisher of World Tennis magazine, King’s star power and the financial backing of Philip Morris.

“My mother ... had an unsurpassed Rolodex, an extraordinary work ethic, and a commitment to the success of the women’s pro tour,” Heldman said. “Billie Jean King was the charismatic star as well as a brilliant publicist for the tour.”

Heldman said on the eve of the Houston tournament, Kramer asked the USLTA (now the USTA) to withdraw the association’s approval of the event. The players were called and threatened with suspension if they competed.

The next day, Gladys met with the players and offered the $1 contracts as protection for them and the event.

“When we held up that $1 bill, that really was the start of women’s pro tennis the way we know it today,” King said. “We talked about the future generations a lot in our meetings.”

PIVOTAL PAIR

Casals and Dalton played in the final of the first Virginia Slims event. The 21-year-old Casals won in three sets.

King and Casals played more than 200 singles and doubles matches in 1971 to promote the new circuit, along with sponsor pro-ams and kids’ clinics. Casals finished her career with 112 doubles titles, winning half with King.

“It was a full-time job on and off the court,” Casals said. “Both Billie Jean and I were very aggressive and also positive. We always felt we could win.”

NEXT GENERATION

King, the winner of 39 Grand Slam titles in singles, doubles and mixed doubles, said the Original 9 wanted a woman anywhere in the world to have the opportunity to compete, earn recognition for her accomplishments and earn a living playing tennis.

Martina Navratilova and Chris Evert, who each won 18 Grand Slam singles titles, brought new skill and star power to the women’s tour and took home $15 million and $8.8 million in career prize money, respectively. Evert received millions more in endorsements off the court.

“All these women were way ahead of their time,” Navratilova said. “They took a huge, huge chance. Look how it paid off.”

A 23-time Grand Slam champion in singles, Williams has earned $92 million during her career. The 10 highest-paid female athletes in the world in 2019 were all tennis players, according to Forbes.

“The Original 9’s belief that girls and women everywhere deserve equality of opportunity — in tennis and in all walks of life — is the enduring vision that guides WTA players,” WTA president Micky Lawler said.

The 76-year-old King would like to see more pay and exposure for women’s pro soccer, hockey and softball.

“Many women’s sports are facing the same challenges we faced 50 years ago,” King said. “The bottom line is we need more investment in women’s sports.”