Coach Zico is refusing to concede defeat in Japan's bid to reach the last 16 at the World Cup finals.

The Blue Samurai lost their opening Group F game against Australia 3-1 in dispiriting fashion in Kaiserslautern on Monday.

Japan took the lead with a controversial Shunsuke Nakamura goal after 26 minutes and held out until six minutes from full time, only for the Socceroos to net three times in a dramatic late comeback.

Zico's men face Croatia next and the Brazilian has set about rebuilding his players' confidence.

"There is no use in standing still and we have to prepare for the next match,' he said.

"There is no use in feeling down. They (the players) have to look ahead with a fresh frame of mind."

Japan also slipped from 2-0 up to draw 2-2 against Germany in one of their World Cup warm-up matches and Zico admitted his players had to learn how to close out games from winning positions.

He added: "We did not do anything after taking the lead. We had two clear goalscoring chances on the counter-attack, but if you do not put the ball in at one end you sometimes concede it at the other.

"We have to change our mindset after the same thing has happened twice.

"We have to study the way we repel any power play the opponents may employ as a last resort.

"We may be able to stop a couple of shots but not for long because of our physical disadvantage. We also have to learn to convert our chances."