The tournament was created in 1990 and was played on indoor carpet courts. In its earliest years, it was held in December but was later moved to the late-September/mid-October period. From 1990 through 1997, the tournament was limited to male players. A women's championship was added in 1998 and was held simultaneously with the men's tournament.
Throughout its existence, the Grand Slam Cup was famous for paying-out the highest prize money of any tournament in tennis. The winner received U.S. $1.5 million. And according to the rules, if the tournament was won by a player who had also won a Grand Slam event that year, the winner received a bonus of U.S. $1 million. So although U.S. $1.5 million was already the biggest prize in the game, as many as four players each year (a quarter of the participants if each of the year's Grand Slam events had had a different winner) had a chance of pocketing U.S. $2.5 million.
The Grand Slam Cup, however, was not recognized by the Association of Tennis Professionals (ATP). Therefore, participants did not receive points in the world rankings maintained by the ATP, and the event was not considered an official career title. (Following discontinuation of the event in 1999, the ATP decided to give the event full recognition retroactively and added it to players' lists of official titles.)
A compromise between the ITF and the ATP was announced on December 9, 1999, by which the Grand Slam Cup was merged with the ATP World Championship (the ATP's year-end tournament), which was also held annually in Germany, giving birth to the Tennis Masters Cup, which would be an official tour event. In the eyes of most tennis fans, this was the end of the Grand Slam Cup because the Tennis Masters Cup is generally viewed as a continuation of the ATP World Championship, not the Grand Slam Cup. The women's tournament was also discontinued after 1999, with just two editions having been held.
A direct result of the merging of the two competitions can still be seen in the qualification rules for the Tennis Masters Cup, which include one notable difference from those of the ATP World Championship. The World Championship was meant to include the top eight players on the ATP world rankings at the end of a season, even though this could mean the exclusion of a Grand Slam champion who had not been able to earn sufficient ranking points the rest of the year. Although the present rules also refer to the best eight players of the year, they ensure the participation of a Grand Slam champion who is unable to earn a top eight ranking at the end of the season. According to the present rules, the top seven players in the ATP Champions Race qualify for the Tennis Masters Cup automatically. The eighth player, however, qualifies only if all the Grand Slam singles champions are among the top eight. Any Grand Slam event champion who is not in the top eight but is still in the top twenty is included to the detriment of the eighth-ranked player. This situation occurred at the 2004 Tennis Masters Cup (in Houston, USA), where the 8th ranked player in the ATP Champions Race, Andre Agassi, was excluded from the event in favor of Gastón Gaudio, who had won that year's French Open but was ranked 10th at the end of the year.
Qualification and seeding for the Grand Slam Cup were not related to ATP rankings. The ITF attributed to players a given numbers of points for their performances in the Grand Slam events (these points were used only to qualify for the Grand Slam Cup). After all four Grand Slam events had concluded, the ITF added up the points, and the 16 players with the most points qualified for the Grand Slam Cup. Although the rules did not assure Grand Slam champions an automatic berth in the event, winning a Grand Slam event was a de facto qualification for the Grand Slam Cup, given the considerable number of points attributed by the ITF to the champion of each event.
The system of play for the Grand Slam Cup was a simple knock-out tournament. Matches in the first two rounds were best-of-three sets, while the semi-finals and final were best-of-five sets. There was no tie-break in a final set.
ITF's Grand Slam Cup qualification points table
Rounds of Grand Slam events only
|Round of 16||75|
|1990||Pete Sampras||Brad Gilbert||6-3, 6-4, 6-2|
|1991||David Wheaton||Michael Chang||7-5, 6-2, 6-4|
|1992||Michael Stich||Michael Chang||6-2, 6-3, 6-2|
|1993||Petr Korda||Michael Stich||2-6, 6-4, 7-6, 2-6, 11-9|
|1994||Magnus Larsson||Pete Sampras||7-6, 4-6, 7-6, 6-4|
|1995||Goran Ivanišević||Todd Martin||7-6, 6-3, 6-4|
|1996||Boris Becker||Goran Ivanišević||6-3, 6-4, 6-4|
|1997||Pete Sampras||Patrick Rafter||6-2, 6-4, 7-5|
|1998||Marcelo Ríos||Andre Agassi||6-4, 2-6, 7-6, 5-7, 6-3|
|1999||Greg Rusedski||Tommy Haas||6-3, 6-4, 6-7, 7-6|
|1998||Venus Williams||Patty Schnyder||6-2, 3-6, 6-2|
|1999||Serena Williams||Venus Williams||6-1, 3-6, 6-3|