90s Tennis Star can be summarized as two of the most successful tennis players of the 1990s, Monica Seles and Andre Agassi. Seles was a Yugoslav-American professional tennis player who won nine Grand Slam singles titles before her 20th birthday. She was the youngest-ever French Open champion at the age of 16. Agassi was an American professional tennis player who won eight Grand Slam singles titles and an Olympic gold medal. He was the first male player to win all four Grand Slam tournaments on three different surfaces. Both Seles and Agassi were ranked world No. 1 in their respective careers and are considered among the greatest tennis players of all time.