One weekend of eye-raising rugby results does not necessarily change the world. Equally, there has never been a day to compare with Saturday. A clean sweep of wins for Ireland, England, Wales and Scotland against the southern hemisphere’s top four teams is unique in the game’s history, despite the south hosting all four of the fixtures.

No Irish or Welsh team had previously won in, respectively, New Zealand and South Africa. Now here they both are, just one final push away from winning a best-of-three series. The same is true of England and Scotland, who also bounced back from first Test disappointment to defeat, in turn, Australia and Argentina and complete the quadrella.

It is a very different scenario from the opening weekend of the July Test window, which ended 4-0 in the south’s favour. But now it is 4-4 entering the closing lap, with all to play for. The four home unions will never have a better chance to make history. Anyone who assumes that, say, New Zealand are guaranteed to reassert themselves in Wellington this Saturday is ignoring creeping reality, because the All Blacks were not so much beaten by Ireland in Dunedin as psychologically unzipped. Of course a multitude of red and yellow cards had an effect, but the mental disintegration was remarkable. Poor decisions, muddled thinking, and that was just up in the coaching box. Poor Ian Foster, just back from Covid, has had an awful month and some reckon he could end up being replaced if Ireland win again this weekend.

It remains a big “if”. Betting against the All Blacks rarely pays off, simply because the pride in the jersey dictates that they cannot afford to be that poor two weeks in a row. But the punchy line delivered by Peter O’Mahony to the All Blacks captain, Sam Cane – “You are a shit Ritchie McCaw, pal” – as tensions rose was not just any old piece of trash talking. New Zealand, especially without Sam Whitelock on the field, are not the irresistible force of old.

Gareth Anscombe celebrates his match-winning kick against South Africa in Bleomfontein
Gareth Anscombe celebrates his match-winning kick against South Africa in Bleomfontein. Photograph: Kim Ludbrook/EPA

Neither are the Springboks on the evidence of their first two Tests against Wales. With a touch more luck Wayne Pivac’s side would be 2-0 up by now, having lost the first Test only by a whisker. While they only won the second via a stunning late angled pressure kick from Gareth Anscombe against a heavily rotated Boks side, emerging players such as Leicester’s Tommy Reffell have done their reputations a power of good.

This Saturday may yet be another story, with the best South Africa players back and pawing the Cape Town turf, but the idea that the world champions can never deviate from their template to sustain success is, by definition, self-limiting. As their head coach, Jacques Nienaber, observed earlier this year: “If you want disaster you must fail to improvise, to build and improve.”

The new world rankings, though, do not lie. By any measure France and South Africa are now the two strongest sides in world rugby and deservedly sit first and second, respectively. After two victories in Japan, France, who have never topped the list before, are on a 10-game run of wins that has equalled their best, set way back in the 1930s.

Ireland are in third with the All Blacks dropping to fourth, their lowest place since the World Rugby rankings began in 2003. Pride will accordingly be at stake this weekend, as well as at the Sydney Cricket Ground, where England and the Wallabies will lock horns for the third and final time.

England’s Sam Underhill playing against Australia.
Sam Underhill was instrumental in England’s redemptive victory over Australia. Photograph: Bradley Kanaris/The RFU Collection/Getty Images

England’s stress-busting win in the second Test in Brisbane, particularly the dominance of their maul in the first half, has just about installed them as favourites to complete a 2-1 success. Australia’s resources were stretched even before their 25-17 defeat at Suncorp Stadium and they have now lost another four players to injury or concussion.

Had they maximised a couple of promising platforms on Saturday the Wallabies might have roared back from 19-0 down, but Eddie Jones’s view is that England will be better again on Saturday. The key to his pack’s improvement from Perth, believes their lock Jonny Hill, was focusing more on what they do best. “We just spoke about being ourselves and each player playing to their strengths within our gameplan,” said Hill.

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“I feel like we were dominant in the forwards. Our drive and scrum got us round the field, put us in good positions and we got a lot of points from it.”

It also sets things up beautifully for next year’s Rugby World Cup. Among England’s pool opponents, for instance, will be Argentina, who must now beat Scotland in Santiago del Estero next weekend. If the Scots prevail they will consider it a serious achievement that will strengthen them further as a squad.

Another 4-0 margin this Saturday would definitely put the cat among the southern hemisphere pigeons. It couldn’t happen again, could it? What is already clear is that rugby is in a levelling-up era where any of the world’s Top 10 sides – Japan lost only 20-15 to France on Saturday – can theoretically beat each other. Whoever wins this weekend, the north-south gap has never been narrower.