World No. 1 Ash Barty has shocked the world of tennis after announcing her retirement at the age of 25.

The Australian made the announcement on social media, saying she was leaving to pursue other life goals: “I’m so happy and I’m so ready,” she said to Casey Dellacqua in an interview. “And I just know at the moment in my heart, for me as a person, this is right.

“I know I’ve done this before but in a very different feeling. I’m so grateful to everything that tennis has given me. It’s given me all of my dreams, plus more, but I know that the time is right now for me to step away and chase other dreams and to put the rackets down.”

Barty has won 15 titles in her career with prize money totalling an estimated $24million.

“I wasn’t sure how to share this news with you so I asked my good friend [retired Australian tennis player Casey Dellacqua] to help me,” Barty added.

“I am so thankful for everything this sport has given me and leave feeling proud and fulfilled.

“Thank you to everyone who has supported me along the way, I’ll always be grateful for the lifelong memories we created together.

“I don’t have the physical drive, the emotional want and everything it takes to challenge yourself at the very top of the level any more. I am spent.”

Barty left the sport in 2014 to focus women’s cricket, then returned in 2016.

WTA chief Steve Simon said Barty was “one of the great champions” in a statement.

“Ashleigh Barty with her signature slice backhand, complemented by being the ultimate competitor, has always led by example through the unwavering professionalism and sportsmanship she brought to every match,” Simon said.