Steffi Graf is the only female tennis player to achieve a Golden Slam in a calendar year.
Graf completed the feat in 1988 by winning all four Grand Slam singles tournaments—the Australian Open, French Open, Wimbledon and U.S. Open—and the Olympic singles gold medal in the same calendar year. This combination is called a Golden Slam because it adds Olympic gold to the traditional Grand Slam.
Her 1988 season was extraordinary for another reason: Graf defeated Gabriela Sabatini 6–3, 6–3 in the Seoul Olympic final. She also became the first tennis player of either sex to complete a calendar-year Golden Slam. Her four major victories came against different opponents in the finals: Chris Evert at the Australian Open, Natasha Zvereva at Roland-Garros, Martina Navratilova at Wimbledon and Sabatini at the U.S. Open.
The wording “in a calendar year” matters. Several players have achieved a career Golden Slam by winning the four majors and Olympic gold across their careers, including Serena Williams and Martina Navratilova. Graf’s unique record refers specifically to collecting all five titles during 1988, not merely over an entire career.