Meares, Australia's most successful track cyclist in history, was unveiled in a special ceremony during which she was cheered by thousands of fans and Olympians at Federation Square.

She was chosen ahead of a panel including racewalker Jared Tallent, who was belatedly awarded a London 2012 gold medal last month, as well as rower Kim Brennan, swimmer Cate Campbell and hockey legend Jamie Dwyer.

“It’s a huge honour [to be chosen]," the 32-year-old said.

"When Kitty [Chiller - the Australian Chef de Mission] flew to Adelaide and told me I was extremely emotional, we were both pretty emotional. 

"It kind of felt like she was proposing to be quite honest. 

"She asked and I said yes!

“I’ve never marched at an Olympic Games, what a way to do it as a first-timer.

“All my life I dreamt of being an Olympian, an Olympic champion and representing Australia I never contemplated or dreamt that I could be the Flagbearer.”

Meares claimed her first Olympic medal 12 years aggo in Athens, winning the 500 metres time trial before claiming bronze in the sprint. 

Four years later in Beijing she produced one of the great comebacks in Olympic history, winning a sprint silver seven months after she broke her neck in a race crash.

She went one better in London when shocking home favourite Victoria Pendleton to the sprint title in a thrilling finale to end a Games in which she also won team sprint bronze.

Meares is also a 10-time world champion and a five-time Commonwealth Games winner.

“Anna is the epitome of what our team represents - respect, humility and excellence," added Chiller.

"She is a role model to many, across all sports and in the community."

 “She was selected for her fourth Olympic Team yesterday and she will inspire not only her cycling teammates in Rio but the entire team.

“Anna is already an inspiration to Australia and I know she will take on this role with the commitment and pride that has been the hallmark of her career to date.”

Meares will follow basketball player Lauren Jackson, who carried the flag at London 2012, while the Beijing Flagbearer was rower turned International Olympic Committee Athletes' Commission member, James Tomkins.

The announcement broke an Australian tradition of only confirming the Flagbearer the day before the Ceremony, but was designed to generate greater publicity ahead of the Games.