Steffi Graf made tennis history in 1988 by winning the Golden Slam, a rare feat that had never been achieved before. He won all four Grand Slam tournaments—Australian Open, French Open, Wimbledon, and US Open—in one calendar year. Not only that, Graf completed his dominance by winning the gold medal at the 1988 Seoul Olympics. This combination of victories made him the only tennis player in history to achieve the Golden Slam, cementing his status as one of tennis' greatest legends.