Rauball and Rainer Koch have been tasked with leading the world's largest national football association after their predecessor Wolfgang Niersbach resigned on Monday over a World Cup 2006 scandal involving a multi-million dollar payment to soccer's governing body FIFA a year ahead of the finals.
"The DFB is currently going through a highly problematic situation. So for the good of our sport, together we need to get to work, the Bundesliga as well as the amateurs," he told Bild newspaper.
"This will take much more time than is expected," said Rauball, who also heads the German Football League (DFL) that runs the top two divisions.
Last month, Der Spiegel magazine alleged that a 6.7 million euro (4.7 million pounds) transfer to soccer's governing body was a return on a loan from then Adidas CEO Robert Louis-Dreyfus to buy votes at a FIFA election in 2000 in favour of Germany's 2006 World Cup bid.
Niersbach, a vice president of the 2006 organising committee at the time, is under investigation for tax evasion in relation to the payment but has denied the claims of a slush fund, accepting only "political responsibility" but insisting he had done nothing wrong.
He said last month, however, he did not know why the payment to FIFA was made in 2005 and had ordered an internal investigation.
World Cup wining player and coach Franz Beckenbauer, who led the 2006 World Cup organising committee, has also rejected the allegations of a votes-for-cash deal but suspicion has grown with the DFB saying a contract between him and former FIFA vice-president Jack Warner, banned from football for life since September, was signed four days before the FIFA vote in 2000.
It offered a series of services, including friendly matches and coaching support to the head of the CONCACAF, the governing body for North and Central America and the Caribbean, which Warner headed from 1990 to 2011.
The DFB said there was no financial offer in the contract, which was never fulfilled, but has urged Beckenbauer, who has not commented on the latest document, to provide answers.
Warner, who sat on the FIFA Executive Committee for 28 years, and 13 other soccer officials and sports marketing executives were indicted in the United States on May 27 on bribery, money laundering and wire fraud charges involving more than $150 million in payments.
(Fixes spelling of Franz in eighth paragraph)
(Reporting by Karolos Grohmann; Editing by John O'Brien)
