Michael Ballack heads home. (Allsport)

Germany coach Rudi Voller urged his players to keep their feet on the ground after watching their 8-0 demolition job on hapless Saudi Arabia.

Miroslav Klose claimed the first hat-trick of the 2002 World Cup finals and Michael Ballack, Carsten Jancker, Thomas Linke, Thomas Bierhoff and Bernd Schneider also got in on the goalscoring act as the Saudis were ruthlessly swept aside.

"It's a fantastic start and it's and great to win by that margin," said Voeller.

"But we have to keep our feet on the ground because we know our opponent wasn't that strong.

"We have to make sure we prepare well for the next match (against the Republic of Ireland on Wednesday)."

Republic boss Mick McCarthy will be hoping his players make a better fist of defending against the Germans than the Saudis did, but Voeller was delighted with his side's hunger for goals.

"From word go we were very committed and did not leave a trace of doubt as to who was going to leave the pitch as winners.

"Miroslav Klose scored a hat-trick and had one assist (laying on Germany's fourth goal scored by Ballack) and, as a former forward myself, I like my players scoring lots of goals.

"But Dietmar Hamann was also very good as a midfield destroyer. He nipped any Saudi resistance in the bud."

There was little Mohammed Noor could say about his side's 8-0 hiding other than: "It was a disastrous display in which we performed really badly.

"We promise our fans that we will do our best in our next two matches."

Hat-trick hero Klose savoured his scoring exploits on the night, but warned the Germans will not have it as easy when they face Ireland on Wednesday.

"It's feels brilliant to have got three goals and an assist in a World Cup match," said Klose.

"I never dreamed we'd get eight goals, but I watched the Cameroon-Ireland game earlier and I can tell you that it will be a different ball game against the Irish."

The 23-year-old Kaiserslautern striker, who scored a hat-trick in Germany's recent 6-2 thrashing of Austria, has taken an early lead in the race to win the World Cup Golden Boot.

But after tonight's match, he was more concerned with having proved himself as a striker on the biggest stage there is.

He said: "It's always been a dream to play a decisive role at a major tournament and I thank my team-mates for making the goals possible.

"I'm glad I've proved to everyone that I can handle the pressure at a big tournament and score goals at this level not just in the Bundesliga."

Captain Oliver Kahn, a virtual spectator in the German goal, also admitted while they kicked off their World Cup in style, the toughest tests are still to come.

He said: "The ball ran well for us and we scored some great goals.

"It was a great start in the tournament and we did not know how good we were before.

"However, we are not going to make the mistake of saying we can now beat any team, but it was important for our confidence.

"We have two more games to play in the group and it will be different then. They will be far more difficult opponents."

Tottenham defender Christian Ziege thinks the hammering may have proved the sceptics wrong, none more so than in Germany.

"The expectancy at home has been very low, however we have proved tonight that we can play good football and we can contest from the word go," said the former Middlesborough and Liverpool player.

"We were under some pressure, but we got off to a good start and were very convincing.

"We will now take things match by match and we will not have it quite so easy again."

Ziege sported a new Mohican haircut, and admitted it may have brought them some good fortune.

"The haircut was just a silly idea me and my wife had the other day," he said.

"Maybe though it turned out to be a good luck charm."

Oliver Bierhoff, who came off the bench to score the seventh, was disappointed with the resistance put up by the Saudis, who are playing in their third successive final.

"I thought they would be a lot stronger," said the former Germany captain.

"We had the physical advantage over them."