'Not right to target a single person'
Boateng, whose half-brother Jerome is in the Germany squad, was responsible for dashing captain Ballack's hopes when his tackle during the English FA Cup final in May ruled the 33-year-old out of the tournament with an ankle injury.
“I do not think it would be right for us to use our emotions or feelings and channel them against a single person,” Bierhoff said.
“Quite irrespective of who is on the pitch for Ghana, we have to concentrate on the game and avoid being provoked, because we will not be playing against Kevin-Prince Boateng, but against Ghana,” he said.
Germany must win to guarantee they advance to the next round, with Ghana currently top of Group D on four points after their 1-1 draw against Australia. Germany are on three points after losing to Serbia, who also have three points.
“It goes without saying that we will approach the game in the absolutely undisputed fair play manner and mindset because personalities are one thing and teams are another,” Bierhoff said.
Berlin-born Boateng, who had played for Germany's youth teams before opting to compete for Ghana just before the tournament, apologised days after the incident and said he never intended to hurt Ballack.
Jerome Boateng criticised his half-brother for not apologising straightaway and said he had broken off any contact with him after arriving in South Africa.
Germany fans quickly declared Kevin-Prince as their 'public enemy number one', setting up hundreds of internet chatrooms to vent their anger.
The Boateng brothers' Ghanaian father, however, launched a scathing attack on German media for painting what he said was a negative image of his son, overlooking far more cruel fouls made by other German players in the past.
“Obviously, we would like to have Michael here (to play). But one player alone cannot decide a game,” Bierhoff said.
Social occasion
Meanwhile, the Germany players, holed up in a luxury, five-star spa and resort surrounded by nothing but scorched fields and red dust, were finally allowed out on Saturday for the first time in two weeks to dress in civilian clothes and enjoy dinner in Pretoria.
Bierhoff said that they had let the players out of their base the previous day for the first time for a social occasion. “Some of us went for a meal in a restaurant,” he said. “It's nice to dress in your civvies and go to another place.”