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Sydney (AFP) - World number one Ashleigh Barty stunned the sporting world by on Wednesday announcing her retirement from tennis aged just 25, weeks after becoming the first home-grown Australian Open champion in 44 years.
Barty is not the only tennis star to quit the game at the height of their powers.
Here, AFP Sport, highlights five other greats who made early exits.
Bjorn Borg
The suave Swede was a dominant force in the men's game for much of the late 1970s and early '80s, winning the French Open six times as well as five successive Wimbledon crowns.
But he abruptly announced his retirement in January 1983, aged 26, a decision generally attributed to burnout.
A year and a half earlier, he had lost to his great rival John McEnroe in the final of the US Open, one major tournament he never managed to win.
Martina Hingis
In 1997 Hingis became the youngest Grand Slam singles winner of the 20th century when she won the Australian Open aged 16 years and three months.In March that year she rose to be the youngest world number one in history.
Wimbledon and US Open triumphs followed the same year with only a French Open final defeat costing her a calendar Grand Slam of all four majors.
But she struggled with ankle injuries, and was just 22 when she retired in February 2003, having won five Grand Slam singles crowns and spent a total of 209 weeks at number one.
"I have been in the game too long to know what it takes to get to the top and I'm no longer capable of it.
Hingis returned primarily as a doubles player in 2006 winning 10 more Grand Slam titles, but never reached another Grand Slam singles final.
Justine Henin
Like Barty, Henin was 25 and on top of the world rankings when the Belgian made the shock decision to retire in 2008 after seven Grand Slam titles but continual struggles with form and fatigue.
"It's the end of a great adventure, the end of something I had dreamed of since I was five," she told reporters as she announced she was quitting.
During a brief return to the tour, Henin reached the 2010 Australian Open final, losing to Serena Williams.She retired for good in 2011.
Andy Roddick
The big-serving American announced ahead of the 2012 US Open that it would be the last tournament of a 12-year career which yielded 32 titles.
It also brought him the world number one spot as well as three heartbreaking Wimbledon final defeats -- going down 16-14 in an epic 2009 final set to Roger Federer -- before his prospects of a permanent place at the top table were swept away by the dominance of Federer, Rafael Nadal and Novak Djokovic.
A fourth-round defeat to Juan Martin Del Potro at Flushing Meadows proved to be the 30-year-old's last elite-level tennis match as he cited injuries and a lack of motivation for his retirement.
In tears as he addressed the crowd, Roddick said: "I've loved every minute of it -- for the first time in my career I'm not sure what to say."
Kim Clijsters
The 23-year-old Belgian retired in May 2007, having packed 34 WTA singles titles into her short career including the US Open in 2005.
She said battling injuries and the constant effort to stay at the top had finally taken their toll.
"It has been more than beautiful," she said."But it's time to hang up my racquet for good."
She made a remarkable comeback between 2009 and 2011, during which she won two more US Opens and an Australian Open.