A sporting legend and one of promising water polo player Cole Miller's grieving relatives will lead a planned-for crowd of thousands in a Brisbane CBD tribute on Monday.
More than 3700 have indicated they plan to attend the King George Square rally for the slain 18-year-old.
Queensland rugby league Immortal Wally Lewis put his hand up to MC the event. His daughter played for the same club as Mr Miller, the Brisbane Barracudas, in the national league.
Event organisers didn't know how many to expect but said they were catering for that number or slightly more.
Plans for the mass tribute began with an 18-year-old Gold Coast woman Monday evening, hours after the much-loved athlete passed away in hospital following an alleged coward punch attack in Chinatown Mall early Sunday morning.
His alleged killers, Armstrong Renata and Daniel Maxwell, were remanded in custody after a court hearing on Tuesday.
Water Polo Australia took over planning for the rally on Thursday as it became clear how large the tribute could become.
Barracudas president Tycho Buningh said Mr Miller's friends and family were "doing it tough", almost a week on from his death.
"It's been very tough on the boys that he played with and even the girls but it's been great having all the family support ready for these players," he said.
"We've had great support from family, from friends, from Queensland water polo, Australian water polo and that's really helped these guys and girls deal with this tragedy."
Mr Buningh, whose son played with the slain teenager, said Cole Miller was a "very promising player" and could have gone on to represent his country.
"I think he could have certainly followed in (older brother) Billy's footsteps and made an Australian team in future years."
Either Billy or Cole's other brother Mitchell are expected to speak at Monday's tribute, from 12.15pm in King George Square.
Supporters were asked to wear green on the day in Mr Miller's honour and Brisbane City Council announced QPAC, the Story Bridge, Victoria Bridge and Redacliffe Place would be lighting up in tribute.
The 18-year-old's death kicked off a storm of discussion over what would be done to prevent similar tragedies in the future, with both the LNP and Labor standing firm on previously stated solutions.
His funeral is planned for 10am on Wednesday at the Cathedral of St Stephen in the Brisbane CBD.