The Athens Olympics lost more big names on Wednesday when women's world 100 metres champion Torri Edwards failed a drugs test and Serena Williams pulled out of the tennis tournament.

Footballers kicked off competition in the Games, two days before the official opening, and hosts Greece had to settle for a 2-2 draw against 10-man South Korea in the men's under-23 tournament -- a comedown after the country's Euro 2004 triumph.

Greece's state broadcaster suffered a short circuit during the first Olympic action and viewers all over the country were left with a blank screen midway through the soccer.

But top Games officials proclaimed everything was in place for a great Olympics, with athletes and visitors flying into Greek capital in record numbers.

There was no escaping news of more drug busts, however.

Edwards, 27, who produced a positive sample for the stimulant nikethamide at an athletics meeting in Martinique in April, was banned for two years by the U.S. Anti-Doping Agency.

The U.S. sprinter, vowing to appeal to the Lausanne-based Court of Arbitration for Sport against the ban, said she was given glucose tablets by her physical therapist who did not know they contained a banned substance.

Spanish cyclist Janet Puiggros Miranda was dropped from the national Olympic squad after a positive drugs test and three unnamed Russians faced exclusion from future competition for doping offences.

"RUSSIAN ROULETTE"

Anyone using performance-enhancing drugs was "playing a game of Russian roulette", Dick Pound, head of the World Anti-Doping Agency, told a Belgian newspaper. The agency planned to run 3,000 to 3,500 doping tests during the Games.

Williams, former world number one and reigning Olympic doubles champion, withdrew complaining of a knee injury. She joins a long list of high profile athletes missing because of doping scandals, poor form or fitness problems.

But organisers said the Olympics were sure to be a success.

"Athens is ready," said Games chief Gianna Angelopoulos, defying the many Cassandras who believed the Greek capital had left it too late to get stadiums built and transport in place.

Bringing the Games back to the land of their birth has meant accommodating the needs of some 10,500 athletes, 5,500 team officials and 21,500 followers from the media.

"Today we have record arrivals at the airport -- about 500 aeroplanes and about 75,000 passengers," said Greek government spokesman Theodoris Roussopoulos.

Security is a top priority for the organisers of the first Summer Olympics since the September 11, 2001 attacks on the United States.

Angelopoulos said Athens had the "most comprehensive, best funded, best staffed security" of any Games.

At a dress rehearsal for Friday's opening ceremony, an airship loaded with electronic surveillance and eavesdropping gear floated in the night sky over the floodlit main stadium and police helicopters buzzed overhead.

PRIDE SALVAGED

Greece salvaged their pride after a bad start to their Olympics with their controversial 2-2 draw against South Korea, down to 10 players after a sending-off.

Their determined fightback in Thessaloniki from two goals down brought relief to the nation after the women's side were humbled 3-0 by a Mia Hamm-inspired United States at the start of the female tournament earlier.

Striker Dimitris Papadopoulos -- one of the heroes of Greece's stunning Euro 2004 feat -- drilled home the equaliser from the spot in the 82nd minute after Choi Won-kwon was harshly adjudged to have fouled Nikolaos Mitrou.

Mexico were held to a goalless draw by Mali in the other Group A match of the men's tournament -- an under-23 competition with three over-age players allowed per team.

In Patras, playmaker Carlos Tevez scored twice and new Manchester United signing Gabriel Heinze was also on target as favourites Argentina thrashed Serbia and Montenegro 6-0.

The South Americans have not won an Olympic gold medal in any sport since the 1952 Helsinki Games.

Also in Group C, Australia drew 1-1 with Tunisia in Heraklio, Crete.

Olympic officials hope to project a modern image of Greece to banish stereotypes of laziness and provide a flavour of the Games' ancient roots, stressing the ideals of competing peacefully and celebrating humanity.

That notion got a lift when table tennis players from North and South Korea agreed to hold a joint training session in a symbolic attempt to start burying decades of Cold War rivalry.

"Politics are far from us as we pursue the Olympic spirit," South Korean team manager Shin Bark-jae told a news conference.