Socceroos, Japan set for must-win opener
With other matches to come against champions Brazil and former semi-finalists Croatia in an unforgiving group, a loss in Kaiserslautern would probably prove insurmountable in the struggle to reach the knockout second round, so the pressure for a result has weighed heavily on both teams.
Australia, in their first finals for 32 years, have lost four of their last five meetings to the higher-ranked Japanese, who are in their third consecutive finals and are the reigning Asian champions.
But the Australians have been transformed under the meticulous coaching of Dutchman Guus Hiddink, who steered Holland and South Korea to the semi-finals of the last two World Cups.
Australia overcame two-time champions Uruguay on penalties to reach only their second World Cup and subsequently have beaten European champions Greece 1-0 and drawn 1-1 with world number three Holland on the road to Germany.
Japan scored twice early in a spirited 2-2 draw against Germany on May 30 and tuned up with a 1-0 win over Malta last weekend.
The 'Hiddink factor' clearly has the Japanese camp concerned, with playmaker Shunsuke Nakamura believing Australia will prove tougher opponents than 1998 semi-finalists Croatia, whom they next play in Nuremberg on June 18.
"I think the Australians are similar to Japan (in style) and perhaps because of that it will make them the most difficult team for us to play against," the Glasgow Celtic midfielder said.
Australia believe they have aerial supremacy over the Japanese and influential English-based attackers Harry Kewell, Mark Viduka and Tim Cahill will be playing against them for the first time in Kaiserslautern.
Japan's squad plan to counter their physical disadvantage with tight marking and specific tactics, with their Brazilian coach Zico heard to bark at his players at training this week: "You won't get any taller overnight. So go mark them tight."
Both camps have had their injury dramas ahead of their showdown with Australian skipper Mark Viduka sitting out training last Thursday with a calf muscle complaint and Kewell working his way back to full fitness after injuring a groin in Liverpool's FA Cup Final win last month.
"I knew it was important for me to back up from Wednesday's Liechtenstein game to play in the Thursday training session and I've achieved that so now I can only look forward," Kewell said.
Japan's Nakamura has been troubled by a sore left hamstring and striker Atsushi Yanagisawa has just returned to full training after 10 days out with an injured right hamstring.
More than anything Hiddink, who takes charge of Russia after the World Cup, has instilled a new belief and steel in his Australian players in just his energising year in the job.
"I have told the players that our goal is to reach the second round and I am convinced that we are going to do it," Hiddink said.
"We have worked a lot on our tactical and technical aspects of our game."