Disappointment reigned at Melbourne's Federation Square as the Socceroos conceded two goals to nil against powerhouse Brazil early Monday.

More than 8,000 people braved the cold, sleep deprivation and crushing crowds to watch the historic match, which kicked off at 2 am (AEST).

Fans were praying for a fairytale finish to Australia's second 2006 World Cup clash against the defending champions, but it wasn't to be.

A hushed murmur engulfed the crowd as Australia forfeited several chances to make it on the scoreboard.

But when the final siren sounded, there were few boos - just respect for the Brazilian team and an acknowledgement that the "down-underdogs" had given it their best shot.

Fan Timothy Luszczak was hoping for a draw but was happy with the Socceroos' performance.

"I don't think I'm disappointed because they won the first game, but against the top team in the world they did very well.

"I think Australia played very well - they played strong, they had a good attacking side.

"But you could tell that Brazil - they had the maturity and the experience over them, but Australia had the heart.

Others were angry at the missed opportunities and some dubious calls by the referee.

"They (Socceroos) deserved to win," Alex Pagani said.

"The referee was crap," his friend Evelyn Canales said.

Earlier, Federation Square was a patchwork of green and gold and fluttering flags as thousands of fans stood shoulder to shoulder urging the Socceroos on to a cacophony of drums, horns and chants of "Aussie, Aussie, Aussie, Oi, Oi, Oi".

But the excitement was marred by some hoolignism .

About five people were arrested, bottles were thrown and smashed and up to 30 flares were set off, according to early police reports.

By 4.30 am most of the crowd had dispersed from Federation Square, but on the other side of town the party was just warming up.

At Copacabana International restaurant in Fitzroy, hundreds erupted around five screens as Brazil stormed to victory.

"I can't explain it, they're all running around with drums and screaming," supervisor Mohammed Omar said.

The crowd was expected to party until dawn, a celebration unlike any Mr Omar had seen, he said.

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