
Graf and Agassi will play world number one Justine Henin and former Wimbledon champion Goran Ivanisevic to raise money for her charity "Children for Tomorrow" which supports children and their families traumatized by war or organised crime.
The former world number one Graf was originally also due to play singles with Henin, but Graf is nursing a light injury which prevented this interesting meeting of the tennis generations.
A spokesman for her foundation told Deutsche Presse-Agentur dpa that income of 500,000-700,000 euros (715,000-1 million dollars) is expected from the event in Mannheim's 8,000-seat SAP Arena.
The funds are to be used for a new trauma clinic in Hamburg, a bigger engagement in South Africa and for a therapeutical kindergarden in Eritrea.
"I want to have fun, make the fans happy and especially do something for children," Graf said recently about the event.
Graf, 38, was born and raised in nearby Bruehl. She won 22 Grand Slam titles and topped the world rankings a total 377 weeks in her professional career 1983-1999.
Graf and Agassi, who got married in 2001, live in the US with their two children. Their son Jaden Gil turned six on Friday and daughter Jaz Elle is four years old.