“I can agree with Uli Hoeness that Franz Beckenbauer was an amazing athlete, a world champion, a great coach coach who then also brought us the World Cup,” Keller told broadcaster Sport1 on Wednesday.

“But you also have to say there is a shadow there.”

Hoeness spoke out on Sunday against the DFB over Beckenbauer’s 75th birthday which he celebrated on Friday, saying the World Cup winner from 1974 (player) and 1990 (coach) had not been given appropriate recognition.

Instead, argued Hoeness, the focus had been on Beckenbauer’s unclear role in how Germany was awarded the 2006 World Cup.

The suggestion Beckenbauer was involved in vote-buying during the bid was “absolutely false,” Hoeness told Sport1.

He knew “very definitely that the money was not used for bribery,” said Hoenss in reference to the 6.7 million euros (7 million dollars) which landed in the bank accounts of Mohamed bin Hammam, a former executive committee member of world governing body FIFA, before the tournament was awarded.

“When Uli Hoeness, as he has said, also has knowledge we would be very happy if he would share that with us or the commission that works it out,” said Keller.

“If he knows something he can gladly share it. And then those who are investigating can work on it. I’m looking forward to that call.”