Under the gaze of over a billion television viewers worldwide, Germany [Images] kicked off the 18th World Cup against Costa Rica on Friday without captain Michael Ballack [Images] but hopeful of success on their home turf.

Coach Juergen Klinsmann's team, the focus of intense media scrutiny for months, is aiming to silence the sceptics with a strong start to the month-long tournament, which is being played in 12 cities across Germany.

But the national team started their quest without Ballack, a gifted playmaker, who has yet to fully recover from a calf injury suffered in a friendly match last week.

Ballack is expected to return for Germany's second match against Poland on June 14. Poland and Ecuador, the other team in Group A, will meet in the western city of Gelsenkirchen at 9 p.m. (1900 GMT) in the only other match on Friday.

"We are hoping for beautiful matches, many goals and fair play," German President Horst Koehler told a cheering crowd of some 65,000 in Munich's new Allianz Arena. "I declare the FIFA 2006 World Cup officially started."

Over one billion television viewers are expected to tune in to the opening match and a cumulative audience of nearly 30 billion will watch at least part of the 64 game schedule which culminates on July 9 in Berlin.

Ahead of the match, a spectacle of dancers in lederhosen and straw-skirts banged on drums and rang giant cow bells under clear blue skies as an emotional crowd waved flags from the 32 countries taking part in the World Cup.

TIGHT SECURITY

Munich, which styles itself as the "capital of soccer" and is home to perennial German power Bayern Munich, was buzzing with excitement.

German and Costa Rican colours dominated the central Marienplatz square, which thumped with festive football tunes, as tourists and locals tucked into Bavarian wurst and beer under a cloudless sky.

"It is a bit like Christmas for a child," said Bavarian Interior Ministry spokesman Rainer Riedl.

"The preparations have run for five years. Now the tree has been decorated, the table set, and we are just waiting for the presents, for this wonderful event to start."

Still, the noise of helicopters overhead and formidable police presence on the streets of Munich were a reminder of the security concerns surrounding the tournament, which is expected to attract 1.5 million foreign visitors.

Many still associate the city with the massacre of Israeli athletes by Palestinian guerrillas at the 1972 Olympic Games and German police have put a massive security net in place to ensure a smooth start to the world's most-watched sporting event.

NATO AWACS radar aircraft will patrol the skies throughout the tournament and 250,000 police are on duty around the country. A comprehensive intelligence-sharing network has been set up with a 24-hour unit in Berlin at its nerve centre.  

"Everyone can come, shout until they lose their voices, have a great time and feel at home with friends but the message to any hooligan or trouble maker is clear: security will function and we are not here to joke around," Riedl said.

Defending world champions Brazil [Images], led by magical Barcelona playmaker Ronaldinho [Images], are favourites to win the tournament again.