How the Wallabies have become a different team with Samu Kerevi at No. 12

It has taken just four Tests for Samu Kerevi to cement himself as one of Dave Rennie's key cogs for the next Rugby World Cup and reinforce the belief that Rugby Australia has little choice but to update its Giteau Law.

A decision on the Wallabies' overseas eligibility policy is expected to come in the next few weeks, but there are already calls for it to be renamed the "Kerevi clause" such has been the centre's impact over the past four Tests.

Kerevi's man-of-the-match performance in Saturday night's 27-8 win over the Pumas was among the finest of his 37-Test career, as the Wallabies made it three straight wins for the first time in four years.

But numbers uncovered by ESPN paint an even greater picture of the Queenslander's impact.

In the five Tests before Kerevi returned to the Wallabies midfield, against the All Blacks in Perth, Australia's midfield had combined for an average of 53 metres and managed only two clean breaks.

With Kerevi back in the No. 12 jersey, partnering Len Ikitau on each occasion, the Wallabies centres are averaging 91 metres per game and have combined for a total 10 clean breaks from only four Tests.

While there are clearly other factors to consider, the return of Quade Cooper and not having to play the All Blacks among them, Kerevi's presence has, according to Wallabies great Tim Horan, completely changed the Wallabies attack.

"I think what he's done basically is helped the whole team go forward," Horan told ESPN. "His post-contact metres have been unbelievable.

"What we saw last year with Hunter Paisami, Samu's taken it to a different level and really allowed Nic White or Tate McDermott, whoever's at scrum-half, and the forwards coming around the corner to get that momentum. And you can't build a platform unless you build that the momentum early, I think he's been outstanding."

At the start of the Test calendar, the Wallabies were playing a lot of "out-the-back" rugby off both 12 and 13, often seeing them caught behind the gainline and hugely susceptible to a rush defence.

That does not mean there is isn't a place for an "out-the-back" in the Australian arsenal, in fact they used that setup to score their only try in the last-gasp victory over South Africa on the Gold Coast earlier this month.

On that occasion, however, it was Kerevi carrying from depth and finding the offload for Andrew Kellaway.

But by having Kerevi at No. 12, the Wallabies have been able to simplify their structure, something Horan saw even greater evidence of on the weekend.

"I noticed quite a different shift in the Wallabies' attack on Saturday, a lot of it was just through the hands, simple stuff where they had adjusted their depth," Horan said.

"But they also weren't playing too many balls out the back because what happens defensively you start to read the balls out the back and if that back runner gets caught you're a long way behind the advantage line.

"So I like the way they're trying to play with a bit more front-foot ball in that first or second phase just to get across that advantage line."

Kerevi has clearly struck up an excellent midfield combination with Ikitau in just four Tests together, as reflected in the numbers above, while he has also helped to take some of the heat off Quade Cooper at No. 10, which has in turn helped the veteran playmaker take a seemingly calmer approach to his decision-making.

Kerevi is also being helped in that regard by another Fijian, Marika Koroibete.

"I think it's two players who have taken the heat off the backline, it's Marika and Samu," Horan explained. "If you look at Reece Hodge's try on Saturday, two defenders went on the outside of Reece Hodge to Marika.

"Both Samu and Marika always attract two defenders, so that's been important for the backline to take pressure of other players and open it up for guys like Quade or Len Ikitau or Hodge and the like."

It remains to be seen just how much of the spring tour Kerevi plays, and for that matter Cooper and Sean McMahon, the latter of whom is expected to see his first Test in four years this Saturday against the Pumas.

While McMahon last week revealed that both he and Kerevi had the overwhelming support of their Japanese club, Suntory, to return to the Wallabies, the duo may not want to push their luck with the Top League powerhouse once the tour moves on from Australia's Test against the Brave Blossoms in Oita on October 23.

But the Fijian would certainly be a massive inclusion for what will likely be three incredibly tough Tests against Scotland, England and Wales on successive weekends through November.

RA is poised to reveal its Giteau Law -- which currently stands at seven years Super Rugby participation or 60 Tests -- plans moving forward, though it is already acknowledged that the likes of Will Skelton, Rory Arnold and Tolu Latu are highly likely to be drafted into Wallabies camp from their French clubs come November.

Reports continue to suggest that an amended Giteau Law threshold could land somewhere around the 30-Test and five years' service to Super Rugby range, a situation that would have seen Kerevi available for the Rugby Championship without the existing leniency shown because of the COVID-19 pandemic.

Horan agrees the 30-Test mark feels about right moving forward, but that the need to keep the Australian Super Rugby franchises as strong as possible also had to be kept in mind.

"I think it's [30 Tests] something like that, whatever the committee come up with it can't be in place for the next five years, it might just have to be flexible for the next couple of years," Horan told ESPN.

"I always look at the fans and what the fans want is the best Wallaby team to be available for every Test match; so if you get beaten by the All Blacks but you have had the ability to select every player from around the world to have the chance to beat the All Blacks, well that's okay.

"But you've still got to try and encourage players to play here in Australia and it's got to be that incentive to play in the gold jersey while you're playing Super Rugby."