Grand Slam (tennis) tennis ball, Martina Navratilova finally did it." Although the ITF recognizes what is now unofficially known as the "non-calendar year Grand Slam" on its Roll of Honour, no subsequent player to win four or more majors in a row—Steffi Graf, Serena Williams, or Novak Djokovic—has received bonus prize money. Combining "the" Grand Slam and non-calendar year Grand Slam, the total number of times that players achieved the feat (of being the reigning champion in all four majors) expands to 18. Three women have won four or more consecutive major titles since 1970, with Navratilova taking six in a row in
1975 Grand Prix (tennis) of titles: No players won their first Grand Prix title in 1975. 1975 Grand Prix (tennis) The 1975 Commercial Union Assurance Grand Prix was a professional tennis circuit administered by the International Lawn Tennis Federation (ILTF) which served as a forerunner to the current Association of Tennis Professionals (ATP) World Tour and the Women's Tennis Association (WTA) Tour. The circuit consisted of the four modern Grand Slam tournaments and open tournaments recognised by the ILTF. The Commercial Union Assurance Masters, Davis Cup Final and Nations Cup are included in this calendar but did not count towards the Grand Prix. The