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
Grand Slam (tennis) have more respect for history, ruled in 1982 that winning any four straight majors constituted a Grand Slam—and offered a $1 million bonus for it [...] But many tennis people, and most writers, and probably most fans, too, did not accept the new rules, and the I.T.F. has dropped the gimmick." Vecsey was only half right: the ITF dropped the "gimmick" of the cash bonus, but it had never changed any rules. However, the ambiguous way the ITF described the Grand Slam in their Constitution led to journalists continuing to make the same assumption as Vecsey over two decades later.