Germany will play against Spain in their second game in Group E at the FIFA World Cup in Qatar on Sunday. Having been upset by Japan 2-1 in the first game, Germany cannot afford to lose again, and their manager Hansi Flick knows it.

"This will be answered on Sunday. Maybe we have another answer to that question, the right answer," Flick said at the pre-game press conference.

Back on Wednesday, Germany blew a 1-0 lead and a dominant first half at Khalifa International Stadium. Ritsu Doan and Takuma Asano scored two goals for Japan in the second half, not only helping their team come back to win, but also teaching the four-time World Cup champions a hard lesson: Germany don't have an unbeatable advantage over Asian teams anymore.

That lesson was already taught by South Korea in the last edition of the World Cup in Russia four years ago. Back then, Germany, as the reigning champions, lost to South Korea 2-0 in their final group game and were eliminated at the early stage.

Germany underperformed in last year's UEFA European Championship as well. They advanced to the knockout stage on a close margin before losing to England 2-0 in the Round of 16 game.

"The last two tournaments were not [good]," Flick said. "We want to avoid a repeat of this. The focus is on concentration. This is the first final for us at the World Cup and that's what it's about – to avoid a repeat of that."

Germany lacked the ability to beat Japan's back line and the best way to fix it is to have a sharp penetrator on the field. Leroy Sane would have been the best option for the team if he hadn't been held back by injury.

"We have to wait for final training and afterwards we can say more [about Sane]," Flock told reporters. "It is good news that he can train. Our medics did a lot of good work and we will see how the training goes."

Japan will play against Costa Rica on Sunday. If the Asian powerhouse wins and add another three points, they will be in a very favorable situation in this group, if not book a spot in the knockout stage.

"I'm proud of our victory over Germany," Japan's manager Hajime Moriyasu said. "But that win doesn't assure us the same against Costa Rica. They have a lot of players with great physical talents and have good orchestrating abilities. Their big loss to Spain in the first game means Costa Rica will spare no desperate efforts against us. We must be ready for that mentally. But first, we need to do our job right."