The Wallabies have come under the microscope for utilising an illegal neck roll at the breakdown area during their 47-26 demolition of the All Blacks in Perth on Saturday.
The tactic involves removing an opposition player from a ruck by grabbing his neck and head area, and twisting him away from the ball.
World Rugby's laws dictate that the penalty for such an infringement is - at least - a yellow card, while the maximum is a red.
After watching a replay of the match, All Blacks flanker Sam Cane claimed he'd fallen victim to the highly dangerous manoeuvre more than once at Optus Stadium.
"To be honest, I wasn't aware of it until I looked at my game yesterday," said Cane. "But there were times when you'd get over the ball and you'd know you were in a good position, and then, for whatever reason, you get taken off it.
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"Sometimes, it was because players were coming blatantly in from the side, sometimes it's those neck rolls. I'm not sure there's much you can do in the game."
World Rugby states that the contact "also applies to grabbing and rolling/twisting around the head/neck area, even if the contact starts below the line of the shoulders".
The perils of such a tactic hit close to home for Cane. He knows how fragile that area can be, after undergoing surgery for a broken neck last year and sitting out of the game for more than six months.
"I remember, at the 2015 World Cup, there was a real clampdown on it. It was taken very seriously.
"It's just one of those things - the laws of the game. They focus on one area and then another area seems to slip off, but I'd like to see it ruled."
The most glaring example from Saturday's game came in the lead-up to Nic White's try, when James O'Connor clearly yanked Anton Lienert-Brown away from the ball by hanging and putting all his weight on the All Blacks midfielder's neck.
Last year, All Blacks prop Owen Franks was penalised for pulling the neck of David Pocock during the Bledisloe Cup test at Eden Park, which forced the Wallabies loose forward out of the second test in Sydney the following week.
That incident sparked an outcry from the Australian team, who campaigned with World Rugby to have it throw the book at Franks.
There's sure to be plenty of extra attention on both the ruck area and referee Jaco Peyper's scrutiny of it in the return test at Eden Park on Saturday.
Join us for live updates of All Blacks v Wallabies from 7:35pm Saturday