Japan national soccer team coach Moriyasu Hajime says his squad beat Germany by refusing to give up.

Moriyasu spoke to reporters after Japan won a stunning victory in its World Cup opener against Germany on Wednesday, beating the four-time champion 2-1 with two second-half strikes.

Moriyasu said his team pulled together in its preparation for the game.

He said his five substitutions made the difference. Among them, Asano Takuma was put on in the 57th minute and Doan Ritsu was deployed 14 minutes later. Their goals sealed the win for Japan.

But Moriyasu sounded a note of caution, pointing out that his team has only won its first match.

He said he is determined to win the coming Group E games without being too cocky about beating Germany. Japan's next game is against Costa Rica, on Sunday.