The US Open is the fourth and final Grand Slam tournament of the year, played annually in late August and early September.

In five notable instances, singles players won the first three events of the year and went to the final major tournament with the opportunity to complete the calendar-year Grand Slam but lost. Otherwise, she would have 21 Grand Slam mixed doubles titles, which is reflected in the above table.The first player to win all four majors in a calendar year and thus complete the Grand Slam was Don Budge in 1938. She also won 11 of the 17 Grand Slam singles tournaments she entered, beginning with the 1962 Australian Championships and ending with the 1966 Australian Championships. In June 2017, Russell Jackson wrote that Court had always held controversial views, which he described as "stubbornly immovable", citing her support for apartheid in 1970 ("South Africans have this thing better organised than any other country, particularly America") and her criticisms of Navratilova in 1990 ("a great player but I'd like someone at the top who the younger players can look up to.

The tournament was given the title "World Grass Court Championships" by the International Lawn Tennis Federation between 1912 and 1923, [87] and was designated a major championship following the abolition of the three ILTF World Championships.

a b Brian Baxter, "Margaret Court's Word of Faith Archived 4 March 2016 at the Wayback Machine", The Skeptics, Vol 27 No 3, Spring 2007. S. Pro Tennis Championships, French Pro Championship and Wembley Championships, standing out, and now considered to have been the professional majors and equivalents to the then-amateur Grand Slam tournaments.

In wheelchair disciplines, two singles players (one quad, one woman) and twelve doubles players (four men, eight women) have achieved it. The International Tennis Hall of Fame states "For sheer strength of performance and accomplishment there has never been a tennis player to match (her). I don't think people realize and put in perspective [that] [t]he Australian Open has come a long way. In 1973, Court set the record for the most singles titles won at a single major (for either women's or men's), with 11 Australian Open titles. Australia Post honoured her, together with fellow Australian tennis player Rod Laver by featuring her on postage stamp.Tennis Australia issued a statement that it "recognises the tennis achievements of Margaret Court, although her views do not align with our values of equality, diversity and inclusion" and said that it is "in the process of working through" how Court's milestone might be included at the 2020 Australian Open. A player who won all three in a calendar year was considered retrospectively to have achieved a "Professional Grand Slam", or "Pro Slam".