Coach Joachim Low made big changes to the team, with Miroslav Klose replacing Mario Gomez up front one of the major surprises.
|MOLE IN GERMANY SQUAD?
|Francois Duchateau | Germany Editor
What's interesting is that not just one paper leaked the line-up, and not just before the clash with Greece. It is not yet clear if the mole is a player or a member of the national team staff.
For Low, this is a serious concern, because tactical nuances can be decisive.
And Bierhoff does not believe it is one of the players who is letting the line-up slip.
"We've asked the players and spoken to them," Bierhoff told reporters. "It is important to surprise the opponent.
"When the line-up leaks five to six hours before kick-off, it becomes difficult.
"We have to make sure that there are no leaks."
Germany are currently on a world-record streak of 15 wins in a row in competitive matches.
They will be in action again on Thursday in the semi-finals of Euro 2012 against the winners of Sunday's match between England and Italy in Kiev.