Racing NSW stewards have suspended betting on The Everest after conducting the barrier draw in private on Tuesday morning.
"The draw was done within our normal protocols on Tuesday morning and only myself and my deputy Philip Dingwall know the results", Racing NSW chief steward Marc Van Gestel said.
"To avoid any perceived integrity risk, Racing NSW has determined that all betting on the 2018 The TAB Everest be suspended commencing at 12pm today (9 October 2018), until the final barriers have been publicly displayed this evening".
Hundreds of protesters shine torches on Sydney Opera House in opposition to controversial advertising for a horse race.
The government sparked outrage by overturning the decision of Opera House management, which had rejected the promotion of the race on the grounds that it breached its guidelines.
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"The specific exemption for the Opera House says you can't do it if it's commercial", Mr Quint said.
"This is one of the biggest events of the year... why not put it on the biggest billboard Sydney has?" said Australian Prime Minister Scott Morrison.
On his Sky News program, shortly after the sails were illuminated, Alan Jones labelled the light-based protest as "childish stuff" from a "latte-sipping mob".
Jones had called for Louise Herron to be sacked during a testy confrontation on Friday after she ruled out allowing words or branding highlighting The Everest to be projected onto the Opera House because "it's not a billboard". "Call Alan" onto the famous building. I think because they'd assume all of the rough and tough people go to the horse racing.
The apology came hours after The Chaser had taken matters into their own hands, with a stunt that saw them project what was "apparently" Jones' real phone number onto a number of Sydney landmarks including the Opera House.