King and the other members campaigned for better pay and conditions for female players; which led to the WTA Tour being formed and this allowed players such as Andreescu to gain equal prize money.

"Every year, I'd look at the prize money and, understanding the sacrifice that went into ensuring it was equal to the men's earnings; it gave me that much more drive to continue to work towards my dream of winning the US Open," said Andreescu in her letter which can be viewed in full on BBC Sport.

"Even with the odds stacked against you, the nine of you had enough faith in yourselves and each other to sign $1 contracts with magazine publisher Gladys Heldman; another trailblazing woman in her own right, to compete in a tournament where the risk was losing your tennis careers.

"With your experiences as an example, the next generation - my generation - of young women is taking charge, using our platforms to speak out for what we believe in and putting it all on the line, regardless of what the outcome or reaction will be. Your leadership has created a powerful platform foundation for us all to speak up for ourselves."

https://twitter.com/BBCSport/status/1304045459749527553?s=20