The Conversation: Billie Jean King and Emma Stone on why 'Battle of the Sexes' matters now

Emma Stone, left, and Billie Jean King at a "Battle of the Sexes" press conference during the US Open. Steven Ryan/Getty Images

Moments before Sloane Stephens took home her $3.7 million winner's check at the US Open -- the same amount pocketed by men's champion Rafael Nadal -- Billie Jean King and Emma Stone huddled with a few media members in a nondescript boardroom dubbed the "situation room" to talk tennis, movie magic and pay equity.

Stone, 28, plays King in "Battle of the Sexes," which recalls the Sept. 20, 1973 exhibition match between the six-time Wimbledon champion against the former men's No. 1 Bobby Riggs (played by Steve Carell).

The movie, which has its nationwide release on Friday, breathes new life into an ongoing conversation regarding power, money and opportunity in not only sports, but all professional fields. Here, King and Stone discuss why they keep charging forward.

On the timing of the film's release:

Billie Jean King: Instead of playing me, I thought you'd be playing the president of the United States. Just sayin'.

But seriously, this film is a blessing. I'm thankful to [producers] Danny Boyle and Christian Colson, as well as [directors] Jonathan Dayton and Valerie Faris. My partner-in-life and love Ilana [Kloss] and I were so excited about Emma playing me from the very start.

I think Emma took a risk with this and she did a fantastic job. Acting is Emma's calling; she's wanted to do this since she was 6 years old. She works hard and is great at what she does. But let's hope Emma doesn't get a big head about the whole thing. Right now, she's got a pea head.

Emma Stone: I like this new nickname; only Billie can say, "Get over here, Pea Head."

BJK: And think about the times we are having -- this conversation of [pay equity] is still relevant, and people will get something out of this film. This movie will carry on into various discussions and dialogues. I want this to count.

ES: I've never played a real person. And now I'm playing Billie Jean King. She's such an inspiring human. She's accomplished great things in the face of adversity. Nothing in life was handed to Billie. She knew she was going be great since she was a child. This role is such an honor.

Stepping back into 1973 -- how did you make that period relevant for today's audience?

ES: For me, I just had to get the physicality of the role. I had to put myself in Billie's shoes. I tried to think about how she had to play this huge match in front of a huge crowd. Imagine the pressure she felt. If she lost to Riggs, she'd be letting down all womankind.

Billie was always questioning her sexuality, but she was all fun-loving, so she had to try to enjoy herself despite the pressure of it all -- I was worried about capturing that.

BJK: I talked to the co-directors [ahead of filming]. And I thought they addressed my sexuality in a moving and authentic manner. And today, kids just shrug it off. It wasn't like that in the '70s. Times have changed so much since then. Now we have gay marriage; back then we barely discussed it.

ES: I also did a lot of studying. The same way athletes study sports' clips. It was a combination of studying Billie and myself. I even did a lot of weird actor-y things, like walking around with pencils in my hands. When you place a pencil in between the fingers, it stretches the hands [demonstrates by putting a chopstick between her fingers]. I did this because Billie has bigger, fuller hands. My hands are little and creepy.

I was walking around with my headphones on listening to Billie's voice and with my pencils in my hands.

The slow progress of pay equity in sports:

BJK: This goes back to the 1800s; at most [tennis] tournaments men and women were always together. They were together on the site. What we had in comparison to what the women in pro basketball or golf have to go through is a little different.

We were always on the same site together and that helped. We had all of the stars in alignment to assist us in our fight, and we knew what we deserved because we saw what the men were getting. When we, the "Original 9," partnered with Gladys Heldman (former publisher of World Tennis magazine), we were able to create the Virginia Slims Circuit so women could have a space to compete for equitable prize money and opportunities. Everyone deserves equitable pay.

ES: We have to correct equal pay everywhere, even in Hollywood. That's a no-brainer.