NEW YORK, NY, USA - When producer Danny Boyle told Billie Jean King he wanted Emma Stone to play her in a movie about the 1973 Battle of the Sexes, the pioneering legend and founder of the WTA was floored.

"She's like the No.1 for me, and that's before she won an Academy Award," King said in an exclusive interview with Tennis Channel and WTA Media. "Emma Stone? Are you kidding? I can't even breathe!" But after spending time with Stone to help her prepare for the role, King quickly realized the pairing was serendipitous. 

"She's 28 and I was 29 at the time. We both have November birthdays. We both have the middle name of Jean. I think it was meant to be."

- Billie Jean King

"She's 28 and I was 29 at the time," King said. "We both have November birthdays. We both have the middle name of Jean. I think it was meant to be."

"I told her, this is really brave of you because I'm still alive. If I passed away you could fake it, but I'm still here. That was an amazing choice to make. I think it's harder. Much harder. It's very brave. 

"Emma didn't want to let me down. That's what she was worried about. Even before they were filming she was so nervous.

"When I was in her trailer talking to her she said 'I just really don't want to let you down.' I said you'll never let me down. She said 'Why?'. I said because I know you bring all of yourself to what you do and that's all you can do. I admire you so much for taking the risk. I could not be happier with their choice. Danny Boyle made that choice."

Written by Simon Beaufoy (The Full Monty), produced by Boyle (Slumdog Millionaire, Trainspotting), and directed by the husband and wife duo of Jonathan Dayton and Valerie Faris (Little Miss Sunshine), Battle of the Sexes stars Stone as King and Steve Carrell as Bobby Riggs, retelling the events surrounding the founding of the WTA Tour and the famous exhibition match that saw King defeat Riggs in the Houston Astrodome on September 20, 1973. King's straight set win over Riggs, a former Wimbledon champion, infused energy and urgency in the women's equality movement in the United States and changed the hearts and minds of the millions of people who watched it.

"President Obama, when I first met him, he said 'I saw the match when I was 12 years old. It helped me raise my daughters to be strong and self-confident.'"

- Billie Jean King

"President Obama, when I first met him, he said 'I saw the match when I was 12 years old. It helped me raise my daughters to be strong and self-confident,'" King said.  

The film recently premiered at the Toronto International Film Festival and the Telluride Film Festival to rave reviews. King was stunned when she walked out on stage with Stone after the screening and was met with uproarious applause.  

"I expected Emma to get a standing ovation, not me," King said. "But these people were probably a little bit older so they're more in my sweet spot. And they brought their children and their grandchildren, which is what I care about because I want the Battle of the Sexes to be relevant and I want it to help now and in the future."

King has already seen the film leave a lasting impact on its stars. Stone and Carrell were paid equally for their work in the film and it was announced last month that Stone is now the highest paid female actress in Hollywood. 

"Emma was so sweet," King said. "She's a great person and she's also fighting for equality. I think this movie changed her a little. You'd have to ask her. I think Emma's feeling stronger, more self-confident I think. She's been speaking out about discrimination quite a bit, equal pay for equal work."

Members of the WTA's Original 9 -- the nine women, who famously broke away from the tennis establishment and signed one-dollar contracts to form the Women's Tennis Association just months before the Battle of the Sexes in 1973 -- attended a private screening of the film during Wimbledon at Olympic Studios. King, the ultimate team player who has always been one to shine a light on others, had made it clear to the filmmakers that she wanted the Original 9 represented in the movie.

"It was kind of fun to see Emma Stone and Steve -- I mean, he had Bobby Riggs' teeth!" said Rosie Casals, King's long-time doubles partner and one of the Original 9. She is played perfectly by Natalie Morales in the film. "He looked like a pretty good jock too. He could swing a racquet and look pretty close to him. Same with Emma Stone."

"The Millenials are the best generation ever in the history to help inclusion. They believe in it. It's just part of their culture."

- Billie Jean King

"I want the younger generation of WTA players to see the movie, I think that is a good start," Casals said. "Even though we've had documentaries, I don't know how many of the top players have seen them. But it means very little to them. It's like your parents telling you about the Depression. It's hard for you to understand when everything is so simple. It's a different life and a different way."

King hopes the film reignites the discussion surrounding the need for equality in the workforce, especially among a generation that has grown up in the perceived afterglow of the progress the Battle of the Sexes helped to bring about. 

"The Millenials are the best generation ever in the history to help inclusion," King said. "They believe in it. It's just part of their culture, they don't even think about it like we had to think about it. I love them for that. I think they are going to make a huge difference."

Battle of the Sexes opens in select theaters on September 22nd and wider release on September 29th.