Up to second in the world and rightly so. Simply superb in knocking out England. The 33-13 scoreline aptly reflects their dominance, other than a fleeting period in the second half.

After rolling the All Blacks in Sydney most knew then that Australia were genuine World Cup contenders. Now they've blown their cover.

Finally, they have a competitive set piece. And they've never lacked for brilliant backs.

In David Pocock they have the world's best breakdown forward; in Bernard Foley an orchestrator capable of handling consuming pressure. The major question mark is depth.

Halfback Nick Phipps is a liability. Can they cover key injuries?

Hard to stop: Schalk Burger. Photo: Getty Images

2. South Africa

Here come the Boks. South Africa's forward pack is beginning to rumble. Only a few short weeks ago Heyneke Meyer told his big men nobody respected them anymore.

Meyer sure got the intended response. His young locks, Eben Etzebeth and Lood de Jager, who was man of the match in the 34-16 win over Scotland with 10 powerful carries and 16 tackles, set the tone and Schalk Burger is back to his best.

Halfback Fourie du Preez, at 33 years old, is pulling the strings. His composure, option taking, control of tempo and box kicks paint him as the perfect puppeteer. Make no mistake, the Boks are back and right in this.

Not at his best: Dan Carter. Photo: Getty Images

3. All Blacks

If the second half against Namibia was a frustrating watch, the error-riddled 43-10 win against Georgia's second stringers was excruciating. The All Blacks may be holding things back but that doesn't excuse 18 handling mistakes in one match.

Scrum issues on opposition ball and Dan Carter's out-of-sync effort were other concerns.

Defence improved dramatically, missing just four tackles, but there's a need to eliminate any potential self-doubt that may creep into the players' minds. Basic skill execution must lift against Tonga.

Heading to the semis? Pablo Matera on the charge for the Pumas. Photo: Getty Images

4. Argentina 

Ireland were poor against Italy, thus miss out on the top five, and the Pumas deserve praise. They fought hard to wear down Tonga and eventually scored five tries in the 45-16 win.

The Pumas are on course for a quarter-final against either Ireland or France. On the evidence of their World Cup to date, they could well make the semis.

Five-eighth Nicholas Sanchez, who scored 25 points against Tonga, fullback Joaquin Tuculet and flanker Pablo Matera continue to impress. With backs and big forwards interchanging like this they have all the skills to cause a major boilover.

The more we see of Maradona dancing in the changing rooms, the better.

Flagging outfit: Sam Warburton's men are feeling the pinch. Photo: Getty Images

5. Wales 

Found out just how taxing short turnarounds can be. Five days after upsetting England at Twickenham, Wales looked out on their feet.

Captain Sam Warburton admitted he felt for Fiji, who were forced to play three of the world's top six teams in 13 days, and other tier-two nations subjected to similar schedules.

Wales enjoyed some favourable calls at the breakdown and were fortunate this match was played in Cardiff. Fullback Matthew Morgan and halfback Gareth Davies, who scored two tries, were standouts.

But the Welsh scrum was a shambles. It's difficult to see them rolling Australia this week. World No 3? Don't know about that.

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