Coach Joachim Loew was delighted by Germany's fight-back in their 2-2 World Cup draw against Ghana on Saturday despite their below-par performance.
Miroslav Klose equalled Brazilian legend Ronaldo's record of 15 World Cup goals after coming off the bench to spare Germany's blushes with the equaliser.
Mario Goetze had given Germany the lead before goals from Andre Ayew and Asamoah Gyan threatened to cause a major upset for the Black Stars in Fortaleza.
"I'm actually quite pleased because we showed great moral to come back from 2-1 down in these temperatures," said Loew about the tropical conditions.
"We took the lead, then conceded two goals from nothing. The players are completely exhausted, but in the end we had a few good chances against a good, combative and skillful team."
But Loew's enthusiasm failed to mask several deficiencies in the German defence that were exposed by Ghana's determined counter-attacks.
Gyan, whose goal saw him join Cameroon legend Roger Milla as the leading all-time African World Cup scorer with five, said that they had played much better than in the 2-1 defeat to the United States.
"We believed in ourselves today," the 28-year-old said.
"I think tactically we were perfect today. Now we definitely have to beat Portugal. We will have to focus but we believe we can beat them."
With the USA playing Portugal in Manaus on Sunday, the result breathes life back into Ghana's hopes of reaching the last 16.
Ghana coach Akwasi Appiah praised his side's never-say-die spirit. "I always believed in us, because we fight until the end," said Appiah, whose side plays Portugal in Brasilia on Thursday.
"It won't be easy to reach the last 16, we only have a point, but it's not impossible. For us to contain Cristiano Ronaldo, who is the best player in the world, will be a team effort, we can't allow him the space to play his game."
The Germans will be knocked from the top of the group if the USA beat Portugal and depending on the result, may have to beat Jurgen Klinsmann's Stars and Stripes in Recife on Thursday to be sure of reaching the knock-out stages.
"We have to see how things go between the USA and Portugal, but the result (against Ghana) hasn't changed our position much," said Loew.
"We know that we still have a good chance of reaching the next round with a win or even a draw, depending on other results."
"But we want to win the next game and stay leaders of the table," he said.
Loew said he hopes to have centre-back Jerome Boateng, who had to come off at half-time against Ghana with a thigh strain, and Thomas Mueller, who suffered a facial cut, fit for the USA clash.
Loew also has the option of starting Klose, who would take sole possession of the World Cup all-time scoring record with another goal.
"It's not been an easy season for him, but he has done it again and got in top shape for a tournament," said Loew, referring to Klose's injury-ravaged season with Lazio.
"From a coach's point of view, it is great to have alternatives like him."