Gregor Paul: Time to super size Scott Barrett

Such is the way of modern test rugby that even at 115kg, Scott Barrett isn't quite big enough yet to have the impact the All Blacks coaches are looking for.

Barrett has everything else he needs to become a powerful addition to the locking stocks.

That much will be confirmed in the next few weeks when he is inevitably given ample game time on the end of year tour in the absence of Brodie Retallick.

What Barrett will inevitably demonstrate in Europe is that he is a quality aerial forward - agile enough to jump anywhere from two to six in the lineout and work the field to take kick offs.

That he's a superb distributor, great reader of space and mobile enough to pop up as a ball carrier as often as the likes of Sam Whitelock and Retallick. He'll show that he's also brave, focused and willing to sacrifice himself for the cause.

But what will most probably also become apparent is that to fulfil his potential, he needs to find some extra weight. The style of rugby the All Blacks will encounter in November will be different.

It's not fair to paint any of the three teams that they will face - France, Scotland and Wales - as lacking in imagination or creativity, but all three will be brutal in the collision zones.

All three build their gameplans around their respective packs and they build their athletes to be more confrontational and less mobile.

The All Blacks coaches are aware of all this now, which is why the longer term goal for Barrett is to find a way to pack some more on to his 1.98m frame.

Size is vital for locks these days because their roles have become uber physical. The dark art of the so-called 'cleanout' has become an increasingly important part of the test match package.

It's a collision zone like no other. It is the metaphorical frontline where there is seemingly endless carnage that serves no particular purpose.

But not so. It's a defined and precise science where players spend hours on the training field learning both how to identify who to target and how to fly in effectively. It might look haphazard, as if its' just smash and bash, but it's not.

And it's also imperative teams get it right as it has a huge bearing on the quality of possession that is delivered.

Whitelock and Retallick do so much that is transparent, but the real value they bring is in their constant ability to wipe out everything in their path and ensure that when ball is taken into contact by the All Blacks it comes out quickly and without any opposition defenders being able to slow it down.

That's the real currency in test football these days and that's largely why the All Blacks want their locks to sit around 120kg, if not be slightly heavier.

Whitelock is 122kg, Retallick 123kg and Patrick Tuipulotu close to 130kg. Barrett is managing to be effective at 115kg but if he can find another five kilos, if not seven or eight and retain his mobility, then he's going to be better equipped to have more of an impact.

As Hansen said before the All Blacks played Argentina in new Plymouth by way of explaining why the 113kg Vaea Fifita was considered only as a blindside: "Our locks are 119kg and 120kg," said Hansen.

"Scotty [Barrett] is a little lighter than that but he'll end up being about that weight. It is a big ask at scrum time in an international scrum to be that light [Fifita's weight] and be considered as a lock.

"Will he go there? You never say never because you don't know what circumstances are that you might have to shove him in there but that is not our aim for him. We want him to be first and foremost a loose forward."