Not since the 1958 FIFA World Cup in Sweden have Wales qualified for the finals of world football's biggest tournament.
They are currently second in Group Four behind leaders Germany after two wins and a defeat in their quest to reach South Africa 2010 and Toshack knows this is their biggest test of the competition.
"This one is the most difficult of the ten games," said the former Real Madrid boss at a press conference here ahead of the game in Moechengladbach on Wednesday. "But my players know everything that you can know about Germany and if they use that they will achieve something.
"We got a 0-0 draw in Frankfurt last November and it would be great if we could repeat that."
Wales will be led by West Ham striker Craig Bellamy who played 80 minutes in Cardiff on Saturday in the 2-0 win over Liechtenstein, but Germany are waiting on the fitness of captain Michael Ballack.
The Chelsea star damaged a calf having scored in die Mannschaft's 2-1 win over Russia in Dortmund last Saturday and a decision on whether he plays will be taken closer to kick off.
But former Newcastle United striker Bellamy says he is looking forward to playing against Euro 2008 finalists Germany.
"I enjoy playing the big teams," he said. "But if we are not 100 per cent focused it will be a hard evening for us," said Bellamy.