"We hope that today's well co-ordinated response sends a clear message that while we are happy for fans to come along and support their favourite player, decisive action will be taken if any patrons, or groups, cross the line of acceptable behaviour at this family event," he said.

The Serbian fans had gathered to support in-form youngster Jelena Jankovic, while the Croats were at the tournament for matches involving Mario Ancic, Karolina Sprem and Ivan Ljubicic.

"They were mostly Serbians ejected as they were upsetting the Croatians," Katherine Jess, police spokeswoman for Victoria State, said.

Proud, but to be proud of? [GALLO/GETTY]

Ancic said he knew nothing about the disturbance, which occurred  as he was cruising to a straight sets victory over Japan's Go Soeda.
  
"No, I had no idea," he said, before defending the Croatian fans.
  
"We are well known for great support but correct support. I don't know [of] any excess ever."
  
Serbian supporters were criticised at last week's Sydney International final when they booed Belgian Kim Clijsters during her win over Jankovic and chanted during her victory speech.
  
Melbourne has large Croatian and Serbian populations and rivalries between the communities has in the past spilled over into violence at football matches.

Community leaders from both sides condemned the violence but blamed each other for the clash.
  
"National pride is one thing but this is unacceptable," Tom Starcevic, Croatian  Community Association secretary, said.
  
"I wasn't there but from what I've seen and heard the Serbs were quite provocative."
  
Serbian Cultural Club president, Toma Banjanin, said Croatian supporters provoked Serbian fans by flaunting their colours.
  
"You didn't see many Serbs dressed that way," Banjanin said. "I  think Croats are always overdoing things, they are always mixing politics with sport."