Lahm, who captained the team to victory in Brazil four years ago and has since retired, told reporters during a visit to a German school in the Russian capital that the team's chances to make the knockout stage were still intact.
"This is an experienced team. The coaching staff is experienced," the former defender said. "They know how to deal with this defeat. Everything is still possible."
Sunday's loss was Germany's first in a World Cup opener in 36 years and the team has not been eliminated in the group stage since the 1938 tournament.
Under coach Joachim Loew, Germany have reached at least the semi-finals in every World Cup or European Championship since he took over in 2006.
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But their performance against Mexico was well below par, raising questions about their title chances and piling pressure on them to win their two remaining Group F games against Sweden and South Korea.
"You could hear already yesterday that players were self-critical," he said. "The German team just did not hit their top form. That can happen because at a World Cup you come up against tough opponents."
Germany next play the Swedes in Sochi on Saturday before facing the Koreans in Kazan four days later.
"A minor setback is not a bad thing to bring the team closer together," Lahm said.
(Reporting by Karolos Grohmann, editing by Pritha Sarkar)
