Rush defence is not a groundbreaking phenomenon but one which clearly the All Blacks grappled to overcome during the Lions series.
More of this is coming their way and improvements are required but the All Blacks are confident of countering the suffocating tactic by essentially refining what they do best.
From club rugby to internationals, every team searches for defensive line speed. The longer you wait for the opposition to come to you, the greater their chance of consistently going forward.
As much as anything else, it is about attitude and connectivity.
Not all rush defence is the same, though. Historically, New Zealand teams have largely focused on simply generating quicker leg speed within their usual alignment.
Alternatives involve sending a shooter to target the inside or outside shoulder, closing down options and forcing opposition to attack in a particular channel.
This is where the Lions' version comes in. Andy Farrell's background in league saw him successfully implement his defensive style with England before moving to assist Joe Schmidt at Ireland, and finally onto the Lions.
The Lions employed variations such as changing the way their wingers defended - narrowly or holding the width - depending on how worried they were about the All Blacks' kicking game.
But, on the whole, the Lions frequently rushed up to try push the All Blacks in towards the breakdown, attempting to limit opportunities to stretch them on the outside.
"It's not new but it's generally uncomfortable," All Blacks assistant coach Ian Foster said. "All Blacks teams have consistently had to deal with rush defence particularly when they go to the UK because it seems that's what a number of teams do up there.
"You can flip it around and say the Lions didn't exactly enjoy our line speed either.
"It's a defensive system purely designed to take time away from attacking teams. Whoever is on the end of it has to be really good at their execution.
"In some ways it's an exciting part of the game because just like not everyone attacks the same, not everyone defends the same now. There's a real challenge for everyone to make sure we're sharp and innovative to look for ways around that.
"When you look at the series they came in with a pretty clear strategy about stopping our width game. That first test surprised them in terms of the way we went about attacking their defence.
"With the end result you'd have to say we had the same number of wins on defence."
Chips in behind and changing angles can help but no one man is responsible for making adjustments and countering rush defence.
Test rugby is never going to offer the same time and space enjoyed at Super Rugby level but those valuable commodities can be created by delivering set piece dominance, quick ruck ball and organising the attack. Deprive the opposition time to re-set their defensive line and holes will appear.
As backline director, the first five-eighth cops much of the blame if the attack fails to fire but, often, it is more the situation the team puts him in that dictates what options are available. Everything starts with generating front-foot ball.
"Overall we had mixed results," Foster admits. "We had some new combinations. In the third test we played much closer to how we wanted to play. We played with a lot more freedom, created opportunities and it was our own fault we didn't take those. But we're pretty confident we created what we needed to."
Every defensive system balances risk and reward. The All Blacks' attacking approach based around playing off halfback Aaron Smith and going direct in the first test succeeded by getting in behind the Lions and forcing them to scramble back all night.
In Wellington, after losing Sonny Bill Williams to a 25th minute red card, the All Blacks were guilty of being too narrow in attack and, therefore, easier targets with ball in hand.
And in the final test, it was basic skills that let them down.
"The whole goal is to impose pressure on people.
"Conversely in attack if we can learn how to deal with that pressure and we get front-foot ball and we're able to go at them then you can exploit it. The series was full of situations like that. They had some victories where they did create pressure on us. But there were other times where we did well with it. We want to get better in that aspect because, clearly, teams don't want to give us time and space and we've got to be better at making it ourselves."
The elephant in the room is no-one wants to allow the All Blacks to play at their desired pace. From making a mess of the lineouts by closing the gap to cynically slowing the ball down at the ruck to pushing the offside boundaries (Maro Itoje the Lions' leader in this regard), the onus is on referees and assistants to properly police these areas.
"We've been saying for a long time there needs to be consistency with the offside line.
"Defences are getting faster and if you give them another half metre then suddenly there's a lot of time taken away. We feel that message is vital for world rugby regardless of what happened in the Lions series.
"The Lions wanted to take every advantage they could and if they get away with that good on them.
"Refereeing the offside line remains one of the key components to enabling teams to have a fair crack at playing."
The Wallabies, in the opening Bledisloe Cup test in Sydney next month, are the next point of call. The All Blacks are well aware their Rugby Championship opponents will studiously study the Lions tape and attempt to adopt successes the tourists had.
"We know they've been working hard to improve their line speed, just as we have. We'd be foolish to think they won't take notice of it but in order to get that you've got to get time to set; time to align, and that comes back to speed of ball."