All-time tennis great Monica Seles celebrates her 46th birthday on December 2, 1973. The former tennis star who represented Yugoslavia and the United States is former world no 1 in women's tennis and also am eight-time grand slam champion. A horrific on-court injury halted her terrific tennis career in 1993. And although Seles returned after a two-year gap, she never was the same player that dominated women's tennis for two successive years.