The Tennis Masters Series in Stuttgart started in 1990. Stuttgarts's mayor Manfred Rommel and Ion Tiriac witnessed the event, and the first year also saw a German triumph - Boris Becker defeated Ivan Lendl in the first singles final of the new indoor tournament.

The following year saw another big name in the winning history: Stefan Edberg. The Swede, a very popular player in Germany, defeated fellow countryman Jonas Swensson in the final. In 1992 Edberg reached the final again but lost to newcomer Goran Ivanisevic. Another German triumph happened in 1993 when Michael Stich won the trophy after having defeated Richard Krajicek in the final match. Stefan Edberg took the title the following year with a revenge over Goran Ivanisevic. In 1995, Krajicek took his revenge over Stich to win the title. The same year Stuttgart became a Mercedes Super 9 tournament. One of the best-remembered finals took place in 1996 when Pete Sampras met Boris Becker to fight for the trophy. Becker won in a hard-fought match against the American. Sampras defeated Becker in the Hanover final just a few weeks later.

In 1997, Richard Krajicek entered the final for the third time, losing to Petr Korda. The following year the Dutchman had more luck and ousted Russia's Yevgeny Kafelnikov. Last year, Krajicek even entered the singles final for the fifth time, but Sweden's Thomas Enqvist proved stronger and conquered his first title in Stuttgart.