The Asian champions gave World Cup hosts Germany a fright when they took a two-goal lead on Tuesday but they had to settle for a 2-2 draw after two defensive lapses.

"We simply can't afford to make those kinds of mistakes," defender Yuji Nakazawa told reporters on Thursday. "We still have a lot of areas we need to work on."

A Naohiro Takahara double was cancelled out by goals from Miroslav Klose and Bastian Schweinsteiger following needlessly conceded free kicks around the penalty box.

"They were great balls in but we shouldn't be committing silly fouls like that," said Nakazawa. "We're just asking for trouble if we do that."

Japan meet Australia in their opening World Cup match on June 12.

Goalkeeper Yoshikatsu Kawaguchi dismissed Tuesday's draw against Germany as meaningless.

"When the World Cup starts the teams we play will have more intensity and will be more fired up," said the former Portsmouth keeper. "It will be totally different."

Japan, who reached the last 16 on home soil in 2002, also face Croatia and holders Brazil in Group F.