Ireland's unexpected 15-6 win over the Wallabies last Saturday in the Rugby World Cup has again brought the scrum into sharp focus. Australia not only lost, but the credibility of their scrum took a pounding.

What also came as a surprise, especially to those who have closely watched them in the Six Nations, was that Ireland had a decent scrum.

This has led to a debate over the significance of the scrum at the World Cup, and Springbok prop Gurthro Steenkamp is an eager participant.

"Ireland were spectacular," said Steenkamp.

"The dominant scrum is going to get rewarded and [the team will] be able to launch better."

The Wallabies have scoffed at the notion that their scrum is fundamentally flawed, pointing rather to moments of inconsistency.

"Our scrum has gone well this year. We put the All Blacks and the Springboks under pressure and dominated them in recent matches so that is not an issue for us," said Wallabies coaching co-ordinator David Nucifora, who put Australia's scrum shortcomings down to lack of concentration.

"What we have to fix is our consistency and our application. But we don't have issues with our scrum," he said.

Nucifora's recollection of recent history may be spot on but as rugby stigmas go, bouts of inconsistency in that set piece are not easily forgotten.

It takes just one lapse in concentration in a dangerous area of the field for teams to suffer, the kind from which they rarely recover in tight World Cup knockout matches.

The Wallabies have been here before. England scrummed them out of the quarterfinal in 2007 and that had very little to do with a few inconsistent set pieces.

Saturday's setback for Australia was in contrast to the improvements to the Wallaby scrum since Robbie Deans became coach. The Wallabies also shunted the Springbok pack in their win in Durban during the Tri-Nations.

Initial signs were encouraging in their World Cup opener against Italy when Azzurri coach Nick Mallett singled out Australia's scrum for praise.

But that changed on Saturday as the Wallaby pack blinked, lost one of their scrums and conceded scrum penalties which proved the difference in the 15-6 scoreline, made up of four penalties, and a dropgoal, to Ireland.