Martina Navratilova is a person.
The Grand Slam tournaments , also called majors , are the four most-important annual tennis events . Martina Navratilova ( Martina Navrátilová [ ˈmarcɪna ˈnavraːcɪlovaː ] ; born Martina Šubertová [ ˈmarcɪna ˈʃubɛrtovaː ] ; October 18 , 1956 ) is a Czech and American retired tennis player and coach . She was ranked in the world 's top 10 in singles for a record 20 consecutive years ( 1975 -- 1994 ) , a span which included 19 years in the top 5 , 15 years in the top 3 , and 7 years as the world No. 1 ranked singles player . She is one of only five tennis players all-time to win a multiple slam set in two disciplines , matching Margaret Court , Roy Emerson , Frank Sedgman and Serena Williams .