Australia v Scotland: Wallabies' weaknesses exposed as side to watch now looks vulnerable

Australia's Scott Sio leaves the field after an injury during the match against Scotland. Photo / Getty Images

Opinion

Many of the Wallabies old demons surfaced today as their World Cup welfare rested on a controversial decision and Bernard Foley's boot.

The five eighths aced the penalty for a 35-34 win against Scotland which will send another tale of injustice into rugby folklore for the losers and open up old wounds about the Wallabies scrum flaws.

Those repeat defects need another overhaul from their scrum guru and former Pumas hooker Mario Ledesma before their semifinal square off against the all-round might of Argentina.

Foley aced the pressure penalty from 29m to clinch this test but his inability to convert three tries left the Wallabies scrabbling to stay ahead of the tenacious Scots.

They had a single point 16-15 lead at the break on the back of a try and flawless goal-kicking from captain Greig Laidlaw and when replacement James Slipper's pass was intercepted by Mark Bennett and converted by Laidlaw, Scotland led with five minutes to play.

As rain began to hit Twickenham, the shock of an unexpected exit creased the expressions of the Wallabies and their coaching bench. Loosehead prop Slipper conceded a penalty at an attacking scrum and the campaign looked in pieces.

Earlier their best loosehead Scott Sio left the field with a damaged shoulder while they had trouble throughout keeping their scrum stable.

The Wallabies had scored five tries to three but faltered with goal-kicks while Laidlaw punished that lapse and the team's growing mistake rate.

The Wallabies needed a break and got it when referee Craig Joubert ruled Scotland were offside from a lineout ricochet. Foley still had to ice the kick and did, as he had in 2014, on fulltime, to claim the Super 15 crown for the Waratahs.

This was more pressure and his kicking had been awry. But Foley bisected his target and as they did, scoring in the last minute of the 1991 World Cup quarterfinal against Ireland to stay in and eventually win the tournament, the Wallabies found a way to eke out victory.

The Pumas will be bursting with optimism about their chances as they have a strong scrum and can match the Wallabies for firepower around the park.

They drove Ireland off their ball at the first scrum and in several scoring bursts blew them away 43-20 in their knockout match.

Nicolas Sanchez showed immaculate goalkicking while the Juan Imhoff, Santiago Cordero and Joaquin Tuculet mix at the back express themselves with distinction.