AUCKLAND - Coach Declan Kidney prefers historians to debate whether Ireland's heart-pumping World Cup victory over Australia was its greatest, but he says it was nice to finally get one over the Wallabies.

The redoubtable men in green produced one of their most spirited performances to fluster and harry the Tri-Nations champions to an abject 15-6 defeat in what felt a 'home ground' atmosphere at Auckland's Eden Park on Saturday.

The driven Irish stunned the Wallabies with their ferocity and commitment to pressure them into error and take charge of Pool C after two games and throw World Cup quarterfinal forecasts out the window.

Such was the tactical supremacy and forwards dominance that Kidney was asked whether it was Ireland's greatest-ever rugby performance, ranking alongside the Emerald Isle's Grand Slam triumphs of 1948 and 2009.

"I think when you're involved in the middle of something it's probably not fair to say," Kidney said.

"It's a privilege to be working with the lads and it's a privilege to be here and we'll enjoy the night but historians can look back and say that.

"We've had a few close calls in the past against Australia, but I think it's fair for others to decide that question ... it's a good reason for a party."

It was Ireland's first victory over Australia in five World Cup encounters after the heartbreak of two one-point defeats - 19-18 in the 1991 quarterfinals and 17-16 in the pool phase in 2003.

"We're fairly pleased with it," Kidney grinned in a massive understatement. "I suppose when you've played a team five times in a competition it's nice to get one over them eventually.

"But it will be meaningless if we don't win the other two matches because we're a long way from qualifying out of our group yet."

Winger Keith Earls was a little more emphatic about Ireland's effort: "It's massive. It's up there with Grand Slams, to beat the Tri-Nations champions."

Kidney quipped a southern versus northern hemisphere final on Oct 23 would not be such a bad outcome after the Wallabies messed up their path through the knockout stages.

Agence France-Presse