Four southern hemisphere giants are preparing for combat over the horizon. With 90% of all men’s World Cups, and having contributed more than 62% of the tournament’s semi-finalists since 1995, they arrive with reputations to uphold. Are they the forces they once were, or are they there for the taking?

South Africa

It’s been 11 years since the Springboks made a clean sweep of Europe. Rassie Erasmus wants to right this wrong by selecting 28 World Cup winners in a squad of 35. Even so, this is a group that has shown signs of evolution. The new attack coach, Tony Brown, has injected flair into a side that boasts the most formidable pack in the game. They can still grind opponents to powder but can now cut them to shreds out wide with an accelerated breakdown and big ball carriers in the trams.

Key question: Who runs the show?

Handré Pollard is a metronome with a laser-sighted boot. Manie Libbok is a magician plagued by the yips off the kicking tee. One of them will have to show something extra to hold down their place when the injured Sacha Feinberg-Mngomezulu returns.

Player to watch: Ox Nché

A prop has never been nominated for World Rugby’s player of the year award. There’s an outside chance that November’s winner will be South Africa’s loosehead. A penalty machine at the scrum and dynamic in the loose, the platform he sets regularly wins matches.

Prediction: 3/3

A full-strength team should see off England while rotated XVs will have too much for Scotland and Wales.

New Zealand

Consecutive defeats by South Africa and a shock loss against Argentina in Wellington means an expectant public will demand a response from Scott “Razor” Robertson’s team. They’re stacked with talent but no longer carry that invincible aura they once brought to every contest. The veterans Sam Cane and TJ Perenara are off to Japan next year and other ageing stalwarts have struggled to paper over cracks at fly-half and in the second row. Patience is needed but might be in short supply if a challenging tour goes sideways.

Key question: How deep can they go?

Before their final Rugby Championship game, New Zealand had conceded 95 second-half points in five matches while scoring 38 in return. Their bench struggled to make good on a strong start against Japan last week and there are serious concerns around a lack of depth beyond the starting XV.

Player to watch: Wallace Sititi

The rampaging loose forward is only 22 but has already caused havoc every time he has donned the black jersey. Adept at blindside or at No 8, he is a threat on either side of the ball and offers options at the lineout.

Prediction: 2/4

England could catch them cold in week one before trips to Dublin and Paris. One win from those three games before a victorious curtain call against Italy in Turin would be par.

Australia

For the first time since he took over as head coach, Joe Schmidt has the pick of the bunch. His phase-play approach has drawn criticism for being overly pragmatic, but there is at least a plan in place to be competitive against the British & Irish Lions next year. Consistency in selection will be key and the inclusions of Will Skelton and Samu Kerevi provide much-needed heft in the tight five and midfield.

Key question: Can Schmidt stick with the same 23?

Rob Valetini is a genuine superstar in the back row and the hooker Matt Faessler, the flanker Harry Wilson and the outside back Andrew Kellaway showed promise, but most others have yet to make the jersey their own. Schmidt will want to know who he can trust and may have to sacrifice a result or two to find out.

Player to watch: Joseph Sua’ali’i

The latest talent to be lured from rugby league, the 196cm, 100kg 21-year-old Sua’ali’i has to deliver on a lot of hype. Rugby Australia paid A$5m (£2.54m) for a three-year contract and will be desperate for the schoolboy prodigy to come good at full-back, wing or outside centre.

Prediction: 1/4

They’re not as bad as some think, though there are still too many holes. They play all Home Nations but will start as favourites only against Wales.

Argentina

A world-class back row, a gifted fly-half, and a frenetic gameplan that gives opposing packs whiplash as they constantly shift the point of contact; coach Felipe Contepomi has gone back to Argentina’s traditional strengths. Their struggles in the wet may be exposed but this is an improved side from the one that finished fourth in the World Cup last year.

Key question: Which Argentina will show up?

Once it was France, now it is the Pumas who are the kings of inconsistency. They beat New Zealand (in Wellington), South Africa (by a point) and Australia (by a record score) but have also been frustrating this year. If they can put together an 80-minute show they’ll challenge anyone.

Player to watch: Tomás Albornoz

A proven star at Benetton, he is now pulling the strings at Test level. Thanks to his composure on the ball and pinpoint kicking, Argentina can set the tempo of games rather than simply react to what’s in front of them.

Prediction: 1/3

France and Ireland should have too much at home which means the game against Italy is a must-win.

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