Under tight security and blue skies, Germany prepared to kick off the 18th World Cup in the southern city of Munich on Friday amid lingering questions over the fitness of captain Michael Ballack.

Juergen Klinsmann's team, the focus of intense media scrutiny for months, will be hoping to silence the sceptics with a strong start to the month-long tournament when they meet Costa Rica at 6 p.m. (1600 GMT).

The German coach must decide whether Ballack, a gifted playmaker and the team's leading goalscorer, is fit enough to take the pitch in the Bavarian capital.

Klinsmann said on Thursday that a calf injury Ballack suffered in a friendly match against Colombia on June 2 would keep him out of the Costa Rica match, but the midfielder may have other ideas.

"I want to play," screamed the headline on the top selling Bild newspaper. German television and radio seized on the story, filling their programmes with renewed speculation on the state of "the country's calf".

"We've worked on the injury intensively," Ballack was quoted as saying in Bild. "I feel fit. I'm no longer in any pain. Whether I play against Costa Rica is up to the coach."

Bild hinted the difference of opinion was the sign of a rift between coach and captain, who have been at pains to stress how good their relationship is.

Assuming Ballack does not play in the Group A opener, he is likely to be replaced by Tim Borowski in central midfield, with Bernd Schneider a top candidate for the captain's armband.

Germany also play Poland and Ecuador in Group A. Those two teams will meet in the western city of Gelsenkirchen at 9 p.m. (1900 GMT) in the only other Friday match.

"LIKE CHRISTMAS"

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

German and Costa Rican colours dominated the central Marienplatz square, which thumped with festive football tunes. 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 buzz 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 champions Brazil are favourites in the tournament, which includes 32 teams and will be played in 12 cities across Germany. The final is set for July 9 in Berlin.