German tennis legend Steffi Graf turns 50

Steffi Graf, who turns 50 this Friday, took to tennis at a young age. According to her father, Peter, she was already hitting balls against a wall in the cellar of the family home at the age of three. In 1981, at the age of 12, she became the first German to win the world youth championship (photo). In 1986 she won her first WTA tournament at Hilton Head, South Carolina.

It was also in 1986 that Graf was named Germany's female athlete of the year for the first time – Boris Becker (third from right) won the award on the men's side. Graf would go on to win the award a total of five times in her career, one more than Becker.

Graf's most potent weapon was her forehand, which helped her to her first Grand Slam win, the 1987 French Open. This would be the first of 22 Grand Slam titles for the native of Mannheim, West Germany. This also propelled her to No. 1 in the women's rankings – which she would hold for a world-record total of 377 weeks.

The 1988 season was Graf's best as she completed the Grand Slam by winning the Australian Open, the French, Open, Wimbledon and the US Open in the same year – a feat only achieved by two other women. However, she was far from done…

Representing West Germany at the 1988 Summer Olympic Games in Seoul, South Korea, Graf beat her Argentine rival Gabriela Sabatini (right) 6-3, 6-3 to win the gold medal in the women's singles and complete what media outlets at the time dubbed the "Golden Slam." Graf also won bronze in the women's doubles.

Both Graf and Becker won their second titles at Wimbledon in 1989. Over her career, Graf would win seven times at Wimbledon, whereas Becker would only win three titles. Two years later, Germany would sweep the single's titles at the All England Championships yet again, with Graf winning on the women's side and Michael Stich beating Becker in the men's final.

Graf dominated the women's game again in 1989, winning 14 tournaments, including three Grand Slams. A year later, though, her father and manager Peter (right) was also making headlines – for an alleged extramarital affair. In 1997, Peter was convicted of tax evasion and sentenced to 45 months in jail – of which he served 25. Graf then fired her father as manager.

The early 1990s were difficult times for the tennis star, not least due to father Peter, who was arrested on tax evasion charges in 1993 – and at times she broke down – as she did here after losing the final of the Australian Open to Monica Seles. Injuries also began to take their toll.

Graf defeated Martina Hingis 4–6, 7–5, 6–2 in the final of the 1999 French Open – the last Grand Slam title of her illustrious career. Two months later, after a hamstring injury forced her to pull out of a tournament in San Diego, she announced her retirement from the game at the age of 30. "I am thoroughly relieved," she said. "I feel wonderful."

After she retired from playing, Graf stepped out of the spotlight almost completely. She and former men's No. 1 Andre Agassi have been a pair since 1999 and the couple were married two years later. They have two children together, son Jaden Gill and Jaz Elle.

Graf founded her own charity, Children for Tomorrow, in 1998. The organization supports children and families who have become vicitims of war, persecution or other forms of organized violence. "The need has constantly grown over the years," Graf said recently. "My greatest wish, of course, would be for there to no longer be any need for the work we do."

Graf, seen here with husband Andre at an exhibition event at Wimbledon in 2009, seldom plays tennis anymore. This she says, is largely due to the hip and knee pain that she continues to suffer from two decades after retirement. All that remains are the memories of a truly great career in the game.