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Australian Open organisers were on high alert today amid fears ethnic clashes between Serbs and Croats that marred the opening day of the Grand Slam tennis championships could erupt again.
Serbia's Ilia Bozoljac and Croatian Marin Cilic are scheduled to contest a first-round match later today and there are fears it could set the scene for a repeat of the soccer-style brawls that stained Melbourne Park yesterday.
It was the first time such violence had flared in more than 100 years of Grand Slam tennis history.
Heavy security is expected around the outside court when the match takes place after thugs vowed to renew hostilities for the second day running.
"We'll definitely be here ... we're coming back," a Serbian supporter clad in his national colours was quoted as saying in today's Herald Sun newspaper.
About 150 fans were evicted from the Melbourne Park grounds yesterday after fighting flared between rival Croatian and Serbian supporters.
Police, however, made no arrests and organisers admitted that they had no way of preventing the fans from returning to the tournament.
"We will monitor them and if we feel there are any issues arising, we will take appropriate action," Open spokesman John Lindsay said.
"It's the first time we've had an incident of this nature ... we're going to keep a close eye on everyone but we're not going to judge every fan on the basis of a few."
Simmering tensions
The brawl follows a decade of simmering tensions between Serbian and Croatian communities in Australia, fuelled by the war in the Balkans after the disintegration of Yugoslavia.
Yesterday's violence came after the breakdown of an informal separation of fans, which usually saw Croatians attend the Open on Monday and Serbians the following day.
But yesterday, with several Serbian and Croatian players due to appear, youths from both communities arrived, many draped in their national flags.
Reports said the trouble began when the two sides began trading insults and racial slurs.
The Sydney Morning Herald website reported that Serbians had chanted "Die Croatians, die" in their language, cheered on by Greeks shouting "Greece, Serbia, Greece, Serbia".
As youths ploughed into one another, police and security guards raced to pull them apart.
Troublemakers were led from Melbourne Park through different exits.
Police reported some minor injuries, but no arrests were made.
Serbian tennis star Jelena Jankovic, the No.11 seed and winner of the ASB Classic in Auckland, said the problem was one which seemed peculiar to Melbourne.
"I think just here in Melbourne there is this kind of problem," Jankovic said after defeating Canadian Aleksandra Wozniak.
"Anywhere else in the world it's fine. When you play a Croatian girl or when there's matches - Serbian and Croatian - it's fine, but here it's just ... I don't know what it is.
"It's just a sport and people should just come and enjoy the game."
Croatian Mario Ancic, who defeated Japan's Go Soeda, said Croatian players had the best fans.
"They're well-known for their good supporting, correct supporting and I've been here many years," Ancic said.
Police are expected to be on high alert today when Croatian Martin Cilic faces Serb Ilia Bozoljac.
- Additional reporting by AAP / REUTERS