The world’s top women’s tennis player Ashleigh Barty has stunned the sport by announcing her early retirement at the age of just 25. “Today is difficult and filled with emotion for me as I announce my retirement from tennis,” she said in a video posted on Instagram. The Australian leaves the sport less than two months after becoming the country’s first home-grown Australian Open champion in 44 years, and winning a Grand Slam tournament on three different surfaces. Barty has won 15 titles, including Wimbledon, played on grass, and the French Open, played on clay. “I know how much work it takes to bring the best out of yourself … I don’t have that in me any more,” she said in the video. “I don’t have the physical drive, the emotional want and everything it takes to challenge yourself at the very top level any more. I am spent.” Barty previously walked away from the game as a teenager in late 2014 after becoming disaffected by the Tour.