The 33-year-old hockey captain, who will retire following the conclusion of the Games, was announced as the host nation's flagbearer by Australia's Governor General Sir Peter Cosgrove and Australian Chef de Mission Steve Moneghetti.

Knowles, due to compete at his fourth Commonwealth Games, was considered a surprise choice as double world 100 metres hurdles champion Sally Pearson was the strong favourite to be given the honour.

He will be tasked with leading the 473-strong team at the Opening Ceremony at the Carrara Stadium on Wednesday (April 4).

"This is amazing," Knowles, gold medallist at the 2004 Olympics in Athens, said. 

"I grew up playing a sport I absolutely love on the grass fields of Rockhampton and I stand here now in front of this group of absolute stars.

"My journey's coming to an end but these 13 days are even more special now.

"It means everything to me."

Knowles, who also won bronze medals at the 2008 and 2012 Olympics in Beijing and London respectively, will make his fourth appearance at the Games.

He is a two-time World Cup winner and has been capped 312 times for his country.

"The flag-bearer is the unofficial captain of the team," said Moneghetti. 

"The position requires qualities far greater than carrying a flag - it is about leadership, integrity and their support for Commonwealth Games."

Knowles is the first hockey player to be named Australian flagbearer at a Commonwealth Games.

Two-time Olympic cycling champion Anna Meares carried the flag at the 2014 Games in Glasgow.

The decision not to select London 2012 Olympic champion Pearson, whose preparations for the Games have been hampered by injury, has fuelled speculation she will play a leading role in the Ceremony.

The 31-year-old, a Gold Coast 2018 ambassador, has insisted she will be fit to race at the event as she bids to claim her third Commonwealth Games gold medal.