The Australian Open, French Open, Wimbledon and the US Open.
All must be in the same category.
A true Grand Slam in tennis is when a player wins all four Grand Slam tournaments in the same year. Otherwise it is just a career Grand Slam, and not a true Grand Slam.
Margaret Court
Arthur Ashe was the first African American tennis player who won 3 grand slam titles.
Jelena Jankovic is a Serbian tennis player. The last three tournaments Jelena Jankovic played in were: the 2013 Porsche Tennis Grand Prix, the Indian Wells, and the Australian Open.
Margaret [nee Smith] Court holds the incredible record in Mixed Doubles titles of winning 12 out of 13 consecutive Grand Slam titles. She won 7 titles in a row. Had she not lost the final of the Wimbledon Mixed doubles title in 1964, she would have achieved 3 consecutive Calendar Grand Slams in Mixed Doubles. Further, she actually won 13 out of 14 Grand Slam tournaments that she entered, having been absent from 3 consecutive tournaments in 1962 after the first of those Grand Slam titles. As history stands, she has achieved one singles Calendar Grand Slam and two mixed doubles Calendar Grand Slams - more Grand Slam achievements than any other player in history.
Roger Federer (SUI) 17 Grand Slam Titles
The four most important tennis tournaments of the world are called Grand Slam tournaments. They are: the Australian Open, the French Open, Wimbledon and the US Open. Any player who wins these four tournaments in a row is said to have won the Grand Slam.
The appropriately named player is Australian tennis legend Margaret Court.
Just 1
Martina Navratilova
The four major tennis tournaments; the US Open, the Open Championships(wimbledon), Roland Garros (French Open), and the Australian Open are known as the Grand Slam of tennis. Hitting a grand slam in baseball scores four runs and is the greatest accomplishment a baseball player can achieve during one at bat. Likewise, winning the Grand Slam of tennis involves winning four tournaments and is considered the greatest accomplishment in tennis. Because "tournament which makes up part of the Grand Slam of tennis" is so long it is usually shortened to "Slam".