Tennis legend Billie Jean King has been a fearless advocate for women’s rights and women in sports since early in her career, but she said there’s still work to do.

King made history in 1973 when she defeated top tennis player Bobby Riggs in the famous “Battle of the Sexes” match. Over 90 million people worldwide tuned into the match, according to BJK’s official website. It is the basis for the 2017 movie of the same name starring Emma Stone and Steve Carell.

Building on her strides for women in sports, King helped found the Women’s Tennis Association and became its first president. She also lobbied for equal prize money for men and women at the U.S. Open, making it the first major tournament to offer equal prize money across sexes.

As the 2025 U.S. Open descends on New York City, King sat down with CNBC’s Alex Sherman for a wide-ranging interview on the state of women’s sports, uniting tennis across men’s and women’s leagues and her perspective on aging gracefully.

On Tuesday, ride-share company Lyft announced it is partnering with King in its “Silver is Gold” campaign in an effort to reframe the conversation around aging.

King said Lyft Silver, a service designed for older adults, is useful because it uses larger font, offers tech support with a live person and matches users with vehicles that are easier to step into. She said it grants older adults freedom and independence.

And while older populations have increasingly turned toward pickleball over the past few years as a source of exercise, King said she’s sticking with tennis.

“I’ve played it a couple of times, but I don’t love the sound,” she said. “As long as I can play tennis, that’s where the magic is for me, when the ball hits the strings.”