Shocking retirements: Five tennis greats who quit at the top

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's a look at five other greats who made early exits.

BJORN BORGThe 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.

Bjorn Borg (AFP Photo)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 HINGISIn 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.

Martina Hingis (AFP Photo)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 HENINLike Barty, Henin was 25 and on top of the world rankings when the Belgian made the shock decision to