Lahm said Germany must justify their place amongst the favourites -- or risk a shock World Cup exit.

Germany lost their two previous matches against Algeria -- 2-1 at the 1982 World Cup and 2-0 in a 1964 friendly. And they are nervously aware that they have not won the World Cup since 1990 as they go into the knock-out phase against Vahid Halilhodzic's Algeria at Porto Alegre's Beira-Rio Stadium.

The winner will play France or Nigeria in the quarter final in Rio de Janeiro on Friday.

"We're in the knock-out phase -- either you deliver or you go home," said the 30-year-old captain.

"Germany has been world champions three times and there aren't that many teams who can say that.

"We have had great teams in the past and this squad has great potential, but we have to take it a round at a time and play aggressively.

"I think we are the better team, but we have to prove that on the pitch."

Having drawn with Ghana in Fortaleza's tropical heat and beaten the United States 1-0 in Recife last Thursday, the cooler climes of Brazil's south are a welcome relief for the Germans.

They are fielding constant questions about the 1982 World Cup in Spain, which remains a sore point in Algeria, three decades after 'the shame of Gijon'.

Despite beating West Germany 2-1 in their group games, Algeria were eliminated after the Germans played out a mutually beneficial 1-0 win over Austria in Gijon.

Coach Joachim Loew has played down any talk of Algerian revenge on Monday.

"We haven't spoken about that, we know it's a subject in Algeria, but most of their players weren't even born," said Loew.

"For us, only (Miroslav) Klose and (Roman) Weidenfeller were alive for that match, so something which took place over 30 years ago is not really a relevant subject."

Loew was equally unimpressed when asked whether he would prefer to meet France or Nigeria in their potential quarter-final.

"France are not in our heads, we have said anyone who underestimates a last 16 opponent is wrong," insisted the 54-year-old.

"It is extremely important at this stage to take it a round by round and not look further ahead.

"We are relaxed and we have enough self-esteem to cope with this. If we believe in ourselves, we should win the match."