Kyle Brown belongs to an exclusive group of rugby players who have tasted victory over New Zealand in a major final.

South Africa's national sevens captain led his country to a stunning 17-12 win over the All Blacks at the Commonwealth Games final in Glasgow last year.

Beating the Kiwis in the 15-a-side game is an even tougher ask - but Australia must do just that if they are to win the Rugby World Cup for a third time tomorrow.

Just like his team did before, Brown believes the Wallabies are capable of an upset over "the best team that has ever played the game," as deemed by South Africa 15s coach Heyneke Meyer.

The 28-year-old flanker said: "If Australia carry on the way they've been playing at the World Cup, which has been phenomenal, they can beat the All Blacks.

"They have destroyed everyone they have faced so far, thanks largely to a very special attack, while the Kiwis have not really been firing on all cylinders yet."

Brown is in town as part of the Springboks outfit competing at the Societe Generale Singapore Cricket Club International Rugby Sevens (SCC 7s) this weekend.

After a three-year absence, the South Africans are front-runners for the Ablitt Cup, along with defending champions Borneo Eagles, a Malaysian invitational outfit, and the development squads of England and France.

The players will also put their rivalries on hold for a live screening of the World Cup final at the Padang tomorrow night.

After finishing 2014 by losing six of seven matches, Australia stormed back under Michael Cheika's leadership to beat New Zealand en route to winning the 2015 Rugby Championship, also including beaten World Cup semi-finalists Argentina and South Africa.

France youth captain Pierre Reynaud expects an open, try-filled encounter between the arch-rivals, even if it goes against history.

The last two finals have been close affairs, with New Zealand beating France 8-7 in 2011 and South Africa breaking England's hearts 15-6 in 2007 in a match decided solely by penalties.

According to Reynaud, All Blacks captain Richie McCaw has to be at his best to stop Australian star forward David Pocock, who has won a turnover every 20 minutes on average at this World Cup.

The 19-year-old said: "Pocock is so impressive both in defence and attack.

"He controls the tempo, can make a long pass, execute offloads - just the model flanker."

Brown agreed, referring to Pocock and tireless team-mates Michael Hooper and Scott Fardy as the "best loose forward trio in world rugby today".

He noted: "They complement each other very well.

"If Pocock and McCaw neutralise each other, who's going to look after Hooper?

"There's also a pivotal battle at fly-half. Bernard Foley has been slightly off in the last two games but if he has his kicking boots on, Australia can use him if the game is tight."

Foley has scored 15 penalties and racked up an impressive 75 points - more than a third of Australia's tally of 205.

England development captain John Brake, however, points to New Zealand's bench as the decisive factor.

After all, few teams can boast substitutes with the playmaking skills of Sonny Bill Williams or the raw power of Victor Vito and Sam Cane - particularly lethal against fatigued opponents.

"We saw in their semi-final against South Africa that the Kiwis pulled away after 60 minutes when their reserves came on," said Brake, 27, who previously played for the Northampton Saints. "Rugby is no longer about numbers 1 to 15. Benches win titles - that is New Zealand's secret weapon."