But the Socceroos will fear nobody when they step onto the South African stage.
"It's a very, very tough game, probably the toughest game certainly in our short history in the World Cup," Neill told a news conference in Durban's spectacular new Moses Mabhida stadium. "But we won't be going into the game with any fear."
Three-times world champions Germany have won their opening match at the last five World Cups and have not been defeated in their first game since 1982, when Algeria beat West Germany 2-1.
Australia have faced Germany before at the World Cup, going down 3-0 to West Germany in 1974. They also lost 2-0 to East Germany at that World Cup.
Organisation and strong defence got Australia through to the knockout stage of the 2006 World Cup in Germany, where they were unlucky to lose to eventual champions Italy.
The Socceroos also played Brazil in Germany four years ago, but 31-year-old Neill said Saturday's game would be tougher.
"Yes, because this is the first game in the tournament and obviously everyone knows that if you lose your first game it becomes very difficult," he said.
"We know we're the underdogs and we know we're going to have to be at our very, very best to get near the German side on the night," said the defender.
Coach Pim Verbeek, who has been criticised for a no-frills, defensive style, said all 23 players were fully fit, but gave nothing away about his final selection.
The Dutchman said he could count on his players to give their all against Germany.
"It's a tough game, but we know the Australian mentality. They will go from the first to the last second of the game and that's what we will need," he said.
Australia exited the 2006 World Cup in the second round when Italy scored a disputed penalty with the last kick of the game after a tackle by Neill.
"The last time it was an unknown journey. We didn't know what to expect. The way that ended kept us all hungry, wanting us to come back and experience it again," he said.
