Some of the All Black forwards feared they were going to pass out. The pressure was that intense. The ball sat in the tunnel of the scrum for five seconds - an interminably long period.
Neither the All Blacks nor France could reach it, so it sat there as both packs tried to push over it. For four seconds, it was stalemate: approximately 1700kg of loading surging through the spines of each respective front-rower. A similar weight was being held by locks Sam Whitelock and Brodie Retallick. Despite the pain, muscles crying out to be free of the pressure and resistance, no one buckled. Eventually, the All Blacks won a few centimetres and from there, the ball was close enough for hooker Dane Coles to strike for it.
"It shows how much pressure there is in the scrums and if someone lifted a foot or didn't stay there and keep pushing it all would have turned to custard," recalls Whitelock of that scrum midway through the second half in Paris. "That showed that both teams weren't willing to give up. Anyone that has been in a scrum, it is full-body movement, it is not one area where you feel it more than another. The longer the ball sits there in the channel - it becomes more of a mental game."
This is scrummaging under the new laws. This will be the epicentre of the battle against England at Twickenham.
It shouldn't be, because the new laws were designed to make scrummaging more of a contest but less of spectacle. The pantomime of collapse and reset was to end and instead, a less volatile system of engagement was introduced ... tests had shown that previously international packs had generated 16,500 newtons of force when they collided into each other under the old rules.
The pre-bind sequence introduced in June has reduced the impact of the hit by 24 per cent but, as has been evident, has created a whole new series of problems. The All Blacks have struggled more than most and England will fancy that the set-piece is the first place they should jam their crowbar.
That stalemate scrum in Paris was not an isolated case: extreme but not isolated. When the new laws were being trialled, the halfbacks determined when they would put the ball in and they didn't have to put it down the centre line.
Under that scenario, scrums were relatively successful in that collapses were reduced and the odds were skewed in favour of the attacking team, without denying the defensive side a fair crack.
"Generally in the scrum I think you can stay strong for probably two seconds," says All Blacks forwards coach Mike Cron. "With the dynamics of it, something is going to give. It is either going to go up, down or be screwed. It can't just sit there when there is that much pressure - two, 900kg packs.
"The reason it [the ball in Paris] sat there is that hookers can't reach the ball. People have a fallacy that it has to be fed down the middle but in reality you just can't get your foot there.
"Guys are so much stronger now. They scrummage at a depth - and their feet are back in a strong pushing position - to be able to lift a leg and to get ahead of where your shoulders are, it can't be done. In the old days we would be higher and closer and you didn't have the same weight going through your body so you could lift a leg."
New Zealand have been one of the slowest major nations to adapt, and that is largely due to the type of athletes they have built. The All Black pack have been conditioned to be explosive and powerful. Under the old rules, they made a high-impact hit that built momentum and then they tried to surge from there.
The new rules have meant the contest proper begins from a different place: the respective scrums are already bearing the weight when the ball comes in and are trying to generate momentum from there.
It's a different type of contest now: one that appears to better suit Northern Hemisphere teams who have more experience of longer scrums.
"It is a different mind-set," says Cron. "Our strength [under the old laws] was that we operated as a technically good eight. With the momentum coming out [of the engagement] and all this arm-wrestling - a lot of the boys in our team have never really been exposed to that whereas in the Northern Hemisphere it has been a bit more that way all the way through. We are catching up."
It's not that All Blacks aren't strong. "Under the old rules we could put one and a half tonnes through a prop's spine. Huge forces. When we push the scrum machine we have one and a half to one and three-quarter tonnes on it and we can push that."
The difficulty is getting the players used to what is called the isometric loading: the effect of pushing against resistance for longer. Scrums are draining the legs more than ever.
"You have to make sure you accelerate hard in those first few steps [out of the scrum] to get the blood back in your legs and you should be fine," says Whitelock.
Week by week, Cron says, his forwards are making improvements. The match against England will be another massive scrum battle for the All Blacks, but it might also be one of the last they endure under the current regime. It's probable that next year the IRB will relent and allow the halfbacks to determine when the ball goes in and referees won't be asked to make sure it goes down the centre line.
"To fix it we just make the channel wider," says Cron. "Like a lineout. The ball doesn't have to go down the middle of the lineout - it just has to be anywhere within the inside shoulder. I think the ball should be fed in straight but the channel just has to be twice as wide as what it is.
"By law, the ball has to go down the centre line which means a part of that ball has to be on the centre line. But for you to hook the ball backwards, you have to get your foot past the centre line to get it back. If it was two rugby balls long instead of one, the hooker could get there and stay dynamic. At the moment he has to lift the foot up and out - and that is why you are seeing them being popped a lot."