Germany face a fight for World Cup survival on Sunday in a must-win clash with Spain as Japan and Belgium look to seal their place in the last 16.

For the second World Cup running, Germany will suffer a humiliating exit in the group phase if they lose their Group E clash with in-form Spain at the Al Bayt Stadium.

The four-time champions were left staring down the barrel of elimination after crashing to a shock 2-1 loss to Japan in their opening fixture on Wednesday.

The prospect of an early German exit – four years after bowing out at the same stage at the 2018 finals in Russia – was practically unthinkable before the tournament.

German coach Hansi Flick insisted on Saturday his team had the quality to bounce back against a rampant Spain team who obliterated Costa Rica 7-0 in their opening game.

"We have a team that has quality, that can implement the things (we are working on), and we are very positive about it," Flick said. "We need to arrive with courage and with faith in our quality for this game against Spain."

Spain coach Luis Enrique meanwhile says his team face a "beautiful challenge" as they chase a win that will see them into the last 16. Luis Enrique cautioned however that Germany's World Cup pedigree – they won their fourth title in 2014 – meant nothing could be taken for granted.

A Spanish victory would mean Japan would also secure their passage to their knockouts if they beat Costa Rica.

Elsewhere on Sunday, 2018 third place finishers Belgium could advance with a victory over Morocco in Group F.

Belgium captain Eden Hazard admitted on Saturday that the Red Devils' vaunted "Golden Generation" is also past its peak – but insisted they remain World Cup contenders.

"To be fair I think we had a better chance to win four years go," the 31-year-old said. (AFP)