Former Germany captain Lothar Matthaus has criticised Per Mertesacker for saying he was glad when the team went out of the 2006 World Cup because of the burden of pressure.
In a wide-ranging interview with Der Spiegel, 33-year-old Mertesacker said he had been "most of all relieved" when tournament hosts Germany lost to Italy.
"I only thought: It's over. It's over. Finally, it's over," Mertesacker said, admitting that the pressure of matchdays could leave him close to being sick.
But Matthaus told Sky: "You don't have to play for the national team -- he did it by his own choice.
"He could have stopped playing if the pressure was too big. To play a World Cup in your home country, and to be carried by euphoria, must not be a burden for you."
Mertesacker said he was looking forward to his new career as the head of Arsenal's academy and wanted to stress the realities of life to those hoping for a career in professional football.
"I want to challenge the system," he said. "We are responsible for the lads who join us. They should not put everything on the football card and neglect education."
Mertesacker said only one percent would reach professional football "and, from the remaining 99 percent, maybe 60 percent will be on the dole."
However, Matthaus said: "He can now say he's happy it's over and he can start a new life. Less pressure, maybe more time for him and his family.
"How can he continue to work in football? How can he explain professionalism to a footballer if he says there's too much pressure? That's not possible."