Tennis legend Billie Jean King has criticized the opposition that does not support equal Grand Slam prize money for men and women. She supports follow Andy Murray's lead by hiring a female coach.

King is the Women's Tennis Association (WTA) founder and believes that men should follow the women's game by removing its ban on mid-match coaching.

When interviewed by reporters and asked about this current issue, she answered "No. It's difficult. You know, sports are a microcosm of society, so it teaches you how the world still perceives gender inequality. It's not fun. It's really sad actually."

Adding "I find men who have daughters are much more understanding. If they have a boy and a girl, for instance, they want both of their children to have equal opportunity. But different cultures also prevent that. Just the way the culture is set up. The way we're brainwashed. So it's difficult. It's very, very difficult, and we've got to keep trying to change things."

According to opposition, men are working harder for the same amount of money as Men's Grand Slam matches are played as the best of five sets while women's are best of three.

King said "I would hope that since we're in this world together, men and women, that we would champion each other more. We would all win. Nobody would lose really. There would be more for everybody. That's what I tried to explain to the men when we were starting professional tennis... They weren't interested. They just thought I was out to lunch. They still do. It's sad. I don't agree with them. I just think if we champion each other it's really important."

For King, there is still much work to do for the league to understand the equality of gender in the sport and this goes for coaching too.

She said "I just think it would be helpful if we had more women coaches. Any time you hurt that human capital, only have half of it, you're missing out on a lot. You just are. It's like having all women coaches and no men. That wouldn't be right either."