Wallabies coach Eddie Jones continued to fend off criticism of his side's faltering rugby World Cup defence on Monday, arguing that recent form would count for little in their semi-final against favourites New Zealand.

Australia and New Zealand meet on Saturday in a replay of their 1991 World Cup semi-final, with the All Blacks overwhelming favourites to reverse that result and reach the final against either England or France.

New Zealand have been praised for their dashing 29-9 quarter-final win over South Africa at the weekend, but there has been scant praise for Australia after their scratchy 33-16 defeat of Scotland, the weakest of the eight quarter-finalists.

Jones admitted his side had not yet played to its full potential, but said the Wallabies could still beat New Zealand.

"We are definitely not where we want to be performance-wise, but we only need to be on Saturday night," he said.

"We are playing New Zealand and we believe we have got the game to beat them."

Jones said the most important thing was that Australia had safely won their pool games and then beaten Scotland, pointing to Wales's exceptional performances against New Zealand and then England as proof that past form would mean little on Saturday.

"It's very hard to get form, it's not like racehorses because teams perform differently on various days," he told reporters.

Rugby World Cup 2003 QFs England outlast Wales France demolish Ireland Kiwis prove too strong for Springboks Wallabies waltz past gritty Scots

"What it comes down to is performance on the night and the team you're playing against."

There was some positive news for Jones, with injured flanker George Smith likely to recover in time for the match. Smith hurt his shoulder and was replaced at half-time against the Scots.

"George has improved overnight, he's gone from being a 50-50 to a 70-30 chance to play," he said.

A fit Smith, however, would present Jones with a selection dilemma. Australia's lineout was overshadowed by the Scots until Smith was replaced by acknowledged lineout jumper Dan Vickerman.

The news was less encouraging for replacement back Matthew Giteau, whose ankle was twisted awkwardly in a tackle after he came on to replace flyhalf Stephen Larkham against Scotland.

Jones said Giteau had injured ankle ligaments and has only an outside chance of being fit for the crucial match.

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"He's working pretty hard on the injury and obviously keen to play, so we will just see how he goes over the next couple of days," Jones said. "But, you know, at this stage he's highly unlikely to play."

Local bookmakers have the defending champions as the least favoured of the four remaining sides, blowing out from Aus $5.25 to Aus $8.00 after Saturday's match.

New Zealand are the new favourites at $2.10, while England have dropped back to $3.20 from $2.80. France are third favourites, firming to $5.50 from $9.00.

Letter writers to major newspapers are also overwhelmingly critical of the home team.

"If I wanted to watch random acts of foolishness, I would go down to Sawtell Seaside Seafoods and throw chips into a flock of seagulls," Edward Hibberd wrote to The Sydney Morning Herald.

"It would have the same level of control, continuity and choreography that the Wallabies displayed across the paddock."