Australian boxer Damien Hooper could be punished for entering the Olympic boxing arena on Monday wearing a T-shirt bearing the colours of the Aboriginal flag.
The 20-year-old light heavyweight, who should have emerged from the tunnel dressed in a red singlet, said he did not regret the gesture.
"I'm an Aborigine representing my culture and my people here at the Olympic Games," said Hooper.
Hooper, the first indigenous Australian boxer to triumph at a junior world title level when he won Youth Olympics Gold in 2010, was ambivalent about being punished for his gesture.
"I didn't say I didn't care," said the fighter.
In the ring on Monday, he pulled off one of his best ever victories, beating America's Marcus Browne -- the first defeat for the United States at the boxing in these Games -- 13-11 to set up a second round clash with Russian fourth seed Igor Mekhontcev.
Hooper, who was a tearaway in his youth before being introduced to boxing by a policeman, is not the first Australian athlete of indigenous origin to fly the Aboriginal colours.
Australian athletics legend Cathy Freeman celebrated her 1994 Commonwealth Games victory in the 200 metres by performing her lap of honour carrying both the Australian and Aboriginal flags.
Undeterred by heavy criticism from Commonwealth officials, and her own team president Arthur Tunstall, she repeated the gesture a few days later after winning the 400m in Victoria, Canada.
The flag, though, was flown at several Olympic venues at the 2000 Olympics in Sydney after heavy lobbying by the National Indigenous Advisory Committee.
Spectators were also allowed to bring them into stadia for events under special dispensation by the International Olympic Committee (IOC).
Under IOC rules no flags can be brought into stadia of nations not competing at the Games, but with the Aboriginal flag they waived the rule.
Its colours red, yellow and black represent the earth, the sun and Aborigines respectively.
