Graf, Steffibyname of Stephanie Maria Graf  ( born June 14, 1969 , Brühl, West Germany [now in Germany]German tennis player who dominated women’s tennis in the late 1980s and ’90s.

Graf began playing tennis with the encouragement of her father, who became her coach. At age 13 she became the second youngest player ever to earn an international ranking. In 1987 she won her first Grand Slam event, defeating Czech-born American Martina Navratilova at the French Open. In 1988 she became the third woman to win all four Grand Slam tournaments (the Australian Open, the French Open, Wimbledon, and the U.S. Open) in one calendar year, and she won a gold medal at the Olympic Games in Seoul, South Korea—an unprecedented feat that became known as the “Golden Slam.”

Graf was known for her intensity, speed, and powerful forehand, and by the 1990s she had become one of the premier players in the world, winning multiple singles titles in the French Open (1987–88, 1993, 1995–96, 1999), Australian Open (1988–90, 1994), and U.S. Open (1988–89, 1993, 1995–96). Her seven victories at Wimbledon (1988–89, 1991–93, 1995–96) were second in number to only Navratilova’s nine. Soon after losing in the finals at Wimbledon in 1999, Graf, who had been plagued by injuries, retired from the sport.

Graf’s retirement did not remove her from the public spotlight. In 2001 she married fellow tennis great Andre Agassi, and the couple became was involved in high-profile charitable causes and appeared in several television advertisements together. In 2004 various charitable causes, including Children for Tomorrow, a nonprofit organization that Graf had founded in 1998 to aid children and families affected by war and other crises. Graf was inducted into the International Tennis Hall of Fame in 2004.