Billie Jean King on Serena’s Grand Slam chances and Kim Davis

By Summer Delaney

“It’s Serena’s to lose or win. She is really in control.”

Billie Jean King thinks Serena Williams will capture the 2015 Grand Slam tennis title. The tennis legend tells Yahoo’s Katie Couric that Williams has what it takes to become the first female since 1988 to win the Australian Open, the French Open, Wimbledon and the US Open all in the same year.

“I think every generation gets better,” said King. “That’s our job; it’s just like a parent wants their child to have a better life, a healthier life.”

King also answered a question many people have: Are we ready to see another “Battle of the Sexes?”

King is still remembered for her 1973 match against male tennis star Bobby Riggs, an event she says she has been asked about every single day since it happened.

“I’ll do an interview with an 8-year-old, I’ll see an 85-year-old that actually saw it. … We had over 30,000 people, [but] I’ve probably had 60,000 people — kidding — tell me they’ve been there,” said King.

Though the Women’s Tennis Association ranks Serena No. 1, John McEnroe told Jimmy Kimmel in August he thinks he could beat her.

King was having none of it, responding that while Serena has a lot on the line, for McEnroe, there is really no downside.

“He’s got nothing to lose,” said King. “He just gets attention and a paycheck.”

In recent decades, King has received attention as an advocate for gender equality and LGBT rights. After the Supreme Court legalized same-sex marriage in June, King tweeted, “Equality For All!”

But not everyone agrees with the decision, including Kentucky County Clerk Kim Davis, who made headlines this month for denying same-sex couples marriage licenses. When asked about the celebration after Davis’ release from prison Tuesday, King said she appreciates Davis’ opinion, but believes there is a complete lack of understanding from Davis and her supporters.

“Every one of us are God’s children,” said King, who was outed by a former partner in 1981. “You got to have tolerance and I find that they live in fear of others, the unknown … what’s important in the way the world is moving is inclusion and more diversity.”

King also spoke publicly for the first time about the fact that her latest match is against atrial fibrillation, a heart condition that causes an irregular heartbeat. Also known as AFib, it affects many as six million people.

“A lot of people have it and don’t know it,” said King. “To understand your stroke risk is very important.”