♪ Mott: The "Battle of the Sexes" was the name given to a match, with a view to putting us women back in our box.

[Cheering and whistling] Narrator: The winner would receive $100,000, and 90 million people tuned in to see the duel.

There was so much on the line for that match.

It was men versus women.

It was very Hollywood, showbiz, but that's the way that she had to get to people.

Howard: There was a lot of dog-whistling in the media coverage.

In the introductory remarks about Billie, Howard Cosell, the leading American sports commentator at the time, said nothing about her accomplishments or all the titles she had won or anything else.

He was talking about her looks.

Cosell: Here comes Billie Jean King, a very attractive young lady, and sometimes, you get the feeling that if she ever let her hair grow down to her shoulders, took her glasses off, you'd have somebody vying for a Hollywood screen test.

There she is.

Woman: I cannot imagine taking that challenge on, and you've got to win because this isn't just about you.

This is about every woman.

Man: You had a lot to lose in the "Battle of the Sexes" game, correct?

We had a lot to lose.

Narrator: The match was the best of 5 sets.

The first to 3 would win.

Mott: If she'd lost, you'd feel the cause of women, ludicrously, would have been set back.

Narrator: King won the first set, 6-4... Mott: She wasn't fighting to play men, she was just fighting for women to have the same chances that men had.

Narrator: quickly took the second set, with Riggs winning just 3 games.

[Cheering, whistling, and applause fade in] ♪ Narrator: Despite his swagger, King made short work of Riggs in straight sets in just 57 minutes.

McEnroe: Forget Bobby Riggs, OK, 'cause Bobby Riggs is like a--a footnote in history at this point.

What Billie Jean King did was the most important thing in the history of women's sport.

♪ King: The men thought it should be all for them, that we should go away.

And I thought, "Who said that?"

[Chuckles] Narrator: That year, the U.S. Open became the first Grand Slam tournament to pay men and women equal prize money.

Barker: I remember, when she won, my coach called me and said to me, he said, "Your hobby has now just become a career."