On September 20, 1973, in a highly publicized “Battle of the Sexes” tennis match, top women’s player Billie Jean King, 29, beats Bobby Riggs, 55, a former No. 1 ranked men’s player. Riggs (1918-1995), a self-proclaimed male chauvinist, had boasted that women were inferior, that they couldn’t handle the pressure of the game and that even at his age he could beat any female player. The match was a huge media event, witnessed in person by over 30,000 spectators at the Houston Astrodome and by another 50 million TV viewers worldwide. King made a Cleopatra-style entrance on a gold litter carried by men dressed as ancient slaves, while Riggs arrived in a rickshaw pulled by female models. Legendary sportscaster Howard Cosell called the match, in which King beat Riggs 6-4, 6-3, 6-3. King’s achievement not only helped legitimize women’s professional tennis and female athletes, but it was seen as a victory for women’s rights in general.

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King was born Billie Jean Moffitt on November 22, 1943, in Long Beach, California. Growing up, she was a star softball player before her parents encouraged her to try tennis, which was considered more ladylike. She excelled at the sport and in 1961, at age 17, during her first outing to Wimbledon, she won the women’s doubles title. King would rack up a total of 20 Wimbledon victories, in singles, doubles and mixed doubles, over the course of her trailblazing career. In 1971, she became the first female athlete to earn more than $100,000 in prize money in a single season. However, significant pay disparities still existed between men and women athletes and King lobbied hard for change. In 1973, the U.S. Open became the first major tennis tournament to hand out the same amount of prize money to winners of both sexes.

In 1972, King became the first woman to be chosen Sports Illustrated’s “Sportsperson of the Year” and in 1973, she became the first president of the Women’s Tennis Association. King also established a sports foundation and magazine for women and a team tennis league. In 1974, as a coach of the Philadelphia Freedoms, one of the teams in the league, she became the first woman to head up a professional co-ed team.

The “mother of modern sports” retired from tennis with 39 Grand Slam career titles. She remained active as a coach, commentator and advocate for women’s sports and other causes. In 2006, the USTA National Tennis Center, home of the U.S. Open, was renamed in King’s honor. During the dedication ceremony, tennis great John McEnroe called King “the single most important person in the history of women’s sports.”

The 1973 match was the subject of a 2017 movie starring Emma Stone and Steve Carell.

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