Asian champions Japan claim that the sweltering weather, which made England struggle to a scrappy 1-0 World Cup win over Paraguay, would benefit his players when they take on Australia.

"Well, it was much more terrible during the Asian Cup," Japan coach Zico, a 53-year-old from Brazil, laughed when asked about the heat which has been gripping Germany after the World Cup got underway on Friday.

Japan's Hidetoshi Nakata (front) controls the ball near coach Zico during a soccer practice session the stadium in Kaiserslautern June 11, 2006.[Reuters]

Japan retained the continental title in China in the summer of 2004 when the mercury soared past 30 degrees Celsius (86 F) with 90-percent humidity and the "Blue Samurai" squad was also feeling the heat from a hostile home support.

The temperature has threatened to reach 30 C during weekend workouts here and it is expected to top that level when Japan clash with Australia in their all-important mid-afternoon World Cup opener in the basin of Kaiserslautern.

"I don't see any problem about the heat because we have ample stamina," Japan captain and central defender Tsuneyasu Miyamoto, 29, said after their final training here Saturday afternoon before they flew out to the match venue.

Japan also shrugged off the heat to whip Bahrain 1-0 away in the middle of the Asian qualifying round a year ago.

Moreover, Japan's domestic J-League season reaches its halfway point in the heat of the summer when European clubs, to which many of the Socceroos belong, remain idle.

"It doesn't matter at all if it's hot," said Japan ace striker Naohiro Takahara, who scored twice in the spirited 2-2 warm-up draw against Germany two weeks ago and will move from Hamburg from another Bundesliga side Frankfurt after the Cup.

"It certainly is hot. But we will be alright because everyone of us have experienced it before," Japan Football Association president Saburo Kawabuchi said.

He noted that most of Japan's squad competed at last year's Confederations Cup in Germany when the weather was similarly punishing.