This is a shocking turn of events for tennis. Barty, only 25 years old, is at the top of her game -- she's less than two months removed from winning her home Australian Open, her third overall Grand Slam singles title -- the other two being the 2019 French Open on clay and 2021 Wimbledon on grass.
Barty has held the world No. 1 ranking for 114 consecutive weeks, according to the WTA Tour.
"I don't have the physical drive, the emotional want and everything it takes to challenge yourself at the very top of the level anymore," Barty said in an Instagram video interview explaining her surprising decision. "I am spent."
Barty is only the second woman to retire with the world No. 1 ranking -- the other being Justine Henin, who also decided to step back at the age of 25, in 2008.
The news sent shock waves through the sports world, with Barty's friends and competitors sending her well-wishes despite their disbelief.
Happy for @ashbarty gutted for tennis 🎾 what a player❤️— Andy Murray (@andy_murray) March 23, 2022
Ash, what can I say, you know I have tears right? My friend, I will miss you on tour. You were different, and special, and we shared some amazing moments. What's next for you? Grand Slam champion in golf?! Be happy and enjoy your life to the max xo Simo@ashbarty pic.twitter.com/WbX7kXnJ1l— Simona Halep (@Simona_Halep) March 23, 2022
What a legend. Incredible inspiration on and off the court. One of the best human beings I've ever met.— Shelby Rogers (@Shelby_Rogers_) March 23, 2022
Our number 1! Best of luck @ashbarty 💞
So much respect for you Ash! Your whole career you've done it your way! Always followed your heart and I hope you keep doing this!! Enjoy golf 🏌️♀️, planning wedding, being home, being with family and dogs 🐶, having good Aussie coffee everyday ☕️ and so many more things!!! pic.twitter.com/ABpceGOOq5— Daria Saville (@Daria_gav) March 23, 2022
Ash, I have no words... actually you are showing your true class leaving tennis in this beautiful way.— Petra Kvitova (@Petra_Kvitova) March 23, 2022
I am so happy I could share the court with you.. tennis will never be the same without you! I admire you as a player and a person.. wishing you only the best! ❤️@ashbarty
Respect it @ashbarty 🙏🏼👏🏼— Thanasi Kokkinakis (@TKokkinakis) March 23, 2022
An inspiration, a magician on the court, a champion of Wimbledon and the Australian Open - World Number One.— Anthony Albanese (@AlboMP) March 23, 2022
As you climbed to the very top, you lifted us all.
Congratulations to Ash Barty on a magnificent career. 🇦🇺🎾 pic.twitter.com/Us2B3Z5Ob0
Happy for you, @ashbarty to go out on your terms but the tennis world will miss a great champion. Love your elegant, athletic style of play and have always been impressed with the way you handle yourself on and off the court. Enjoy the next chapter. 💚💛— Tracy Austin (@thetracyaustin) March 23, 2022
Ash, you always did everything the exact way YOU wanted to do it and not what others told you to do. Your own way, own path.. That is what I appreciate and respect so much about you. I will miss my slice buddy on tour 🙏 Congrats champ and all the best! #1 @ashbarty— Kirsten Flipkens (@FlipperKF) March 23, 2022