Naomi Osaka & More Female Tennis Stars Reflect on the WTA's Legacy as U.S. Open Begins

01 of 13

The WTA's "Original Nine"

50 years ago, in 1970, nine trailblazing female athletes - now dubbed the "Original Nine" - changed the sport of tennis forever.

The players - including Billie Jean King, Rosie Casals, Judy Tegart Dalton, Kerry Melville Reid, Valerie Ziegenfuss, Kristy Pigeon, Nancy Richey, Julie Heldman and Peaches Bartkowicz - signed $1 contracts with Gladys Heldman, publisher of World Tennis Magazine, to compete independently of the men, at the $7,500 Virginia Slims Invitational in Houston.

Bouncing off of that success, three years later, the Women's Tennis Association was founded by King to promote equality in sports.

Today, the WTA's players are among the highest earning athletes in sports. Some of the most prominent players reflect on what the 50th anniversary - and the organization - means to them alongside exclusive new photos as the 2020 U.S. Open kicks off in New York.

02 of 13

Naomi Osaka

Naomi Osaka, 22, tells PEOPLE that the "Original Nine" are "definitely inspirational, and a lot of what I have today is because of their endeavors."

"I actually started my Play Academy with Naomi Osaka with similar intentions: to get more girls active in athletics," Osaka - who was the first Japanese player to reach WTA's world number 1 ranking - says. "I heard a statistic that girls drop out of sport at twice the rate that boys do by the time they reach 14. Tennis is everything to me and has shaped me into the person I am today so if I can inspire and help other girls pursue their dreams in sport, that's a legacy I can be proud of."

03 of 13

Naomi Osaka

Osaka - the highest-earning female athlete ever, who is also a consecutive two-time Grand Slam champion - tells PEOPLE that it's "really important that girls and women around the world have the chance to compete in sport at the highest level."

"I appreciate all that has been done by women in the past to allow me to pursue my dreams today," the athlete says. "Tennis is one of the few sports where the prize money pool is similar or the same as men, but I know that in most other sports, that's not the case. I will do my best to continue to push for equality both on and off the court."

04 of 13

Sofia Kenin

The 21-year-old Sofia Kenin - who won her first-ever Grand Slam tournament at the 2020 Australian Open - tells PEOPLE that the WTA has made "things better for women's tennis."

She adds of the "Original Nine": "I really respect them and am really grateful to them for everything that they've done."

05 of 13

Sofia Kenin

Kenin - who is currently ranked as the fourth best women's tennis player in the world - is "very proud" to be part of the WTA.

"It's an honor and I'm really happy and looking forward to being on the WTA Tour throughout my career," she says.

Kenin also looks to King for inspiration, and particularly admires the trailblazer's quote, "Champions keep playing until they get it right."

06 of 13

Monica Puig

Monica Puig - who was the first-ever Olympic gold medalist for Puerto Rico in 2016 - says this 50th anniversary is "more than just about tennis."

The 26-year-old tells PEOPLE, "It is about women striving to achieve excellence. It is about beating a stereotype that women aren't equal to men. It is about showing power, strength and resilience day in and day out. In the world of sport, the WTA is fighting every day for equality in sports and we as individuals are giving young girls the ability to dream that one day, they too can make a difference."

07 of 13

Monica Puig

WTA U.S. Open — Women’s Tennis Association (WTA)

Puig - who was named best female athlete of the 2016 Rio Olympic Games - says she's "proud to be a part of the WTA and this sport because I feel like I am making a positive impact of future generations."

"Whether it is encouraging the youth to get out and be active, or being a role model for young kids around the world, I feel like I am leaving a positive footprint in this world for generations to follow. I am very proud to be representing this amazing association and all that is does."

08 of 13

Madison Keys

Madison Keys, 25, tells PEOPLE "my career would not be a career without" the "original nine."

Keys - who is the winner of 5 WTA titles and is currently ranked 14th in the world for women's tennis players - says "everything that they sacrificed, I am very, very thankful for."

09 of 13

Madison Keys

"I think one of the things that makes me most proud about being a part of the WTA is that it started with such an amazing stance and such strong women who were willing to risk everything for them, but also all of the future generations. To be a part of that and to try to carry that on, and to be part of that legacy, that makes me proud," Keys - who last made it to the U.S. Open women's singles finals in 2017 - says.

10 of 13

Coco Gauff

Coco Gauff, 16, tells PEOPLE that "as a young player coming up, I've been given some privileges that other players in the past didn't have."

That luxury is not lost on the athlete, who is ranked 51st in the world among women's tennis players .

"I probably wouldn't be playing here and there wouldn't be a WTA Tour if it wasn't for the 'Original Nine,' so I'm super thankful for them to use their voice and pave the way and give us players in the future a chance to compete at the highest level."

11 of 13

Coco Gauff

The teen - who famously defeated her idol Venus Williams in her first-ever appearance at Wimbledon last year - says she's "proud to be a part of the WTA Tour because it's a global sport."

She continues, "You have players from different backgrounds, different countries, all coming together to play one sport and also the equal prize money - tennis is one of the few sports where women and men make the same amount of money. That's one of the reasons why am proud to be WTA player."

12 of 13

Amanda Anisimova

Amanda Anisimova, 19, tells PEOPLE the importance of the 50th anniversary is not lost on her.

"I think that's so important for the sport to keep growing and it's amazing to see how much it's grown and how many new players there are," the teen, who is the second youngest player in the WTA Top 100, adds.

13 of 13

Amanda Anisimova

The athlete - who is ranked 28th in the world for female tennis players - thinks it's important to look back on the WTA's legacy to see the future of women's professional tennis.

"I'm super proud to be a part of the WTA because we have so many strong and independent women," she tells PEOPLE. "When you look at Serena [Williams] and how much she has done for the sport and she keeps doing, and then Billie Jean King who started this all for us, it's just amazing to see how the WTA got started and how we keep improving."

Discover the full story of the Original 9 on the WTA's website.