Billie Jean King vs Bobby Riggs. The inside story of how a champion battled to change the world, is now on the new Sky Documentaries channel.
The Battle of the Sexes documents the showdown between US Open champion King and ex-pro Bobby Riggs on September 20, 1973.
At the time, King was 29 and Riggs was 55, yet despite being retired from tennis for 14 years Riggs was adamant that he could beat any woman.
King eventually beat Riggs in straight sets, 6-4 6-3 6-3 in front of more than 30,000 fans at the Astrodome in Houston, Texas, an estimated 50 million people in the United States and 90 million worldwide. The match is now described as a milestone moment in women's sport.
In the same year as The Battle of the Sexes, King formed the Women's Tennis Association (WTA) and the US Open became the first tournament to offer equal prize money.
Now all Grand Slam tournaments offer equal prize money, but in the remaining tournaments, women earn 20 per cent less than men.
"I really wanted to inspire the younger generations to go forward and fight for equality," said King, "because every generation does have to start over, every generation does have to fight for it."
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