Champion supermaxi Wild Oats was struck by lightning while it underwent final preparations out of the water for the Sydney to Hobart.
Wild Oats was in her cradle at Woolwich Dock on Sydney Harbour when a bolt of lightning struck the top of the 45-meter high carbon fibre mast.
Sandy Oatley, spokesperson for the Oatley family, said it has been "a major blow for them on the eve of the big race".
Although it is unclear if any of the yacht's carbon fibre rigging was damaged, the 10 million volt-plus discharge from the lightning destroyed a number of vital electronic instruments.
However, despite damage to her electronics, the 100-footer is still expected to be on the start line.
"I'm sure our great team will have everything ready for the start on Boxing Day. There is no stopping them," Oatley told Sailing World.
Rivals supermaxi Black Jack skipper Peter Harburg has offered repair with Wild Oats shore team manager, Paul Magee, flying to Brisbane to see what equipment exists in Black Jack's warehouse that could replace instruments damaged by the strike.
"That's the spirit that exists in this level of ocean racing," Oatley said.
"We might be arch rivals on the racecourse, but we're all supportive of each other when necessary."
The yacht had failed to complete the Sydney to Hobart last year after suffering hydraulic ram damage and in 2015 retired from the race due to sail damage.
Skipper Mark Richards said he hoped this would be the third and "final strike of bad luck for Wild Oats XI".
"Two years ago the mainsail shredded in a storm; last year the canting keel hydraulic system keel failed, and now we've been hit from the heavens," he said.
Richards added that rigging checks would continue tomorrow but believed no further damage would be found.
Another supermaxi, LDV Comanche, was docked alongside Wild Oats XI when the storm struck but was not impacted by the lightning strike.