Stephanie Gilmore has been bashed over the head with a metal pole outside her apartment in Tweed Heads, Australia.
The four-time world surfing champion was struck twice and suffered a fractured wrist and cuts to her head.
The 26-year-old man fled immediately after the attack on a pushbike.
Gilmore was taken to the Tweed Heads Hospital for treatment but left the medical unit soon after.
The Australian surfer had clinched a historic third consecutive Triple Crown of Surfing, a few days ago, in Hawaii.
The man was charged with several offenses and jailed at the Tweed Heads Police Station, with a refused bail.
"There was an incident in which I was attacked at my property," Gilmore said.
"It was a completely random act in which I was a victim in the wrong place at the wrong time. It is now a matter for the court."
"I have sought medical attention and am on my road to recovery in high spirits. I look forward to getting back in the water in six weeks."
"In the meantime, I’m staying mentally and physically fit every way I can."
"I have fantastic support from my family and friends and look forward to resting up for a fresh start in the New Year."