Legend Gregan expects Olympics sevens upset

The 1999 Rugby World Cup winner told AFP he expected traditional stalwarts, such as New Zealand, Australia, and South Africa to be in for a shock when they come up against the sport's "sleeping giants".

"Some of the powerhouses might sit back and think because they've played rugby for a long period of time that guarantees them a win," Gregan, rugby union's most-capped international, said.

"But they'll be rudely awakened because there are some sleeping giants I believe in this format," Gregan, in Hong Kong for the southern Chinese city's famous sevens tournament, added.

"China is definitely a sleeping giant," the 39-year-old said, also picking out Malaysia, the Netherlands, and Spain as upcoming countries likely to cause a shock in four years' time.

The former Australian captain, who played 139 Tests between 1994 and 2007, said lesser-known rugby nations were in the process of putting together "the best structures and programmes available", believing they can win a medal.

China, currently ranked 69th in the International Rugby Board World Rankings, is better known for dominating table tennis and badminton at the Olympics.

The country finished second behind the United States in the medals table at the London games last summer.

Rugby last featured at the Olympics in 1924 when the 15s format was played.