On Monday, March 8, the world will celebrate International Women’s Day.

This year’s theme, #ChoosetoChallenge, is dedicated to further set aside bias and stereotypes, and to help forge a gender-equal world.

In the world of sports, women have fought hard for equal recognition, respect and pay. Since the early 1970s, tennis has led the charge for unity.     

“My grandfather used to always say, ‘It's about much more than the ball,’" WTA President Micky Lawler said. “I wondered, when I was a child, what he meant by that, and what he meant was that sports drives a platform, and so, you want to use that platform to its greatest benefit. It's about virtues, the virtues of being competitive, of working hard, of being the best that you can be. And then to create social change and to call for social justice.

Said Laura Ceccarelli, COO of APG Sports and tournament director of the Zhengzhou Open: “Since I was a kid, I always felt that if I wanted to have something in life that I would have to work hard at myself and believe everything was possible. I have been lucky to have incredible women around me that proved determination and perseverance are key to our own strength and to the confidence to reach our goal.

“Being so close to incredible athletes in the tennis world was a real inspiration to me. I have seen them going through very difficult and challenging times and still fight so hard on-court and perform.”

In recognition of International Women’s Day, players – past and present – came together to express some of the challenges they have endured and how they have persevered.  

Sania Mirza, former doubles World No.1

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Coming from the subcontinent, I think playing tennis itself was a big doubt that everybody had. I’ve been challenged from a very early age in my life, when I decided to play tennis and dreamt of playing Wimbledon one day. Every step of the way there were doubters, but obviously I am glad to have proven them wrong.

I think that a lot of confidence came from within. My mom is one of the strongest women that I know. She was adamant and put in so much hard work for us to be where we are, for me to be where I am and I derive a lot of strength through her. She was the one who always believed that nothing is impossible.

Never be scared to be the first person to do something, whether from your family or your country. If you believe in yourself and you work hard and love what you do, don’t ever be scared to be out-of-the-box. Don’t ever be scared to choose that for yourself and put everything that you have behind it.

Francesca Jones, World No.211

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Women have to build off each other. Ultimately, every woman has so much potential if they continuously put the work in and commit themselves. Just continue to believe in yourself and keep believing that you can achieve what you want.

Every human being has doubts. It would be unrealistic of me to say that I feel 100 per cent confident in my ability on a daily basis. I’ve had people say before, especially when I was about 7 or 8 years old, that I wouldn’t be able to play tennis. That basically put fire in my belly to keep pushing forward and to commit to the sport and prove to myself that I can do whatever I set out to do. I am very lucky to have unbelievable parents who have always believed in me and given me the confidence to do what I need to do, and that makes it a little bit easier.

Petra Kvitova, World No.10

WTA Tour

I had a few doubts in my life - of course, especially after the attack. I didn’t know if I ever could hold a racquet and play tennis again after surgery. I heard many voices saying I would never ever play again at a high level. My dad and my mom never gave up. I think it was very natural to have this attitude from them.

Never give up. That’s probably my motto. When you're down, you never give up and try to be better.

Greet Minnen, World No.109

Palermo Ladies Open

After playing two years on the pro circuit, I started getting troubles with my back. It was like a stress injury - I got it when I had just come out to everyone. It was something new for me and my family and I think it wasn't easy to adapt for the first time when I told them I fell in love with the same gender.

I had a lot of good role models in tennis. Martina Navratilova did so much for tennis and for the LGBT community. I would just tell anyone to be yourself, to not feel ashamed. You always have to be yourself and try to be happy, and that's the most important thing in life.

Demi Schuurs, doubles World No.12

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When I was younger and starting to wear men’s clothes, I doubted myself. But I was just being myself, and I think that's really important in life. I don't care what other people think about me and I just enjoy life, be myself and be happy. If you want to wear boys' clothes, if you want to love a boy or girl, it doesn't matter - be yourself, be happy and enjoy life.

Sloane Stephens, World No.44

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I come from a long line of incredibly strong women who have always given me the confidence to be myself and the resolve to keep striving. Find your hype team! Root for each other and pick each other up when times are tough.

Leslie Allen, former World No.17

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As a Black American living in the United States, I am going to face racism, sexism and microaggressions. My ability is going to be questioned, and I am going to be asked whether I belong in a certain space. That’s just how it is. But I learned at an early age how to deal with that. And I also learned that I needed to be twice as good to achieve. So, when you face those types of things, this is what I want you to know: It’s not about your inability, it’s about their inability to see your value and to appreciate and acknowledge your brilliance. It’s not about you.

One sentence changed my life, and it came from two-time Wimbledon and US Open champion Althea Gibson. She looked at me and said, "Leslie, with your wingspan, you need to think about winning WTA tournaments."  I had just told her, "I’d like to be in the main draw." It changed everything and I changed my goal. Within a couple of years, I was winning WTA tournaments. Set your goals higher than you believe you can achieve. You’ll be surprised with what you can do.  

Madison Keys, World No.19

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Throughout my entire career, there have been a lot of times of doubt within myself. I think that’s life, honestly.

I really feel good when I’m trying to support other people, highlighting other people. With my Kindness Wins foundation, I have been really inspired by all of the people whom we have gotten to know and highlighted, and seen all of the amazing work they have been doing.

It’s finding a mantra that’s yours and what you believe in, and I think doing the small things could really help.

Kiki Bertens, World No.11

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After my Achilles surgery, I doubted myself if I could overcome my rehab and practice in full again. My parents have always told me that if you want something then just go for it. And try to do your best in whatever you are doing.

Ons Jabeur, World No.31

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I had surgery on my wrist a few years back and I wasn’t able to play for a few months. When coming back, people doubted me and basically told me to stop playing tennis. I always knew that I could overcome this, and I came back and even won my first junior title.

My family stood by me and helped me get through this difficult period. They always made me believe in myself. I also had this person inside me that always believed that I could be a great tennis player, encouraged me to overcome this and this whole package helped me be where I am today.

You have an inner power, everybody does. Try to use that power and make it worth your hard work.

I have been very fortunate to find my place at organizations where being a woman would not prevent you from your goals. There are many closed doors that women have to face, but I truly believe that gender equality will continue to become a reality in the not-so-distant future.