League: Plotting kiwis' domination

Sonny Bill Williams won't be there. It's doubtful Frank Pritchard will be either. Manu Vatuvei might struggle, given his injury troubles over the years, and Simon Mannering is adamant he won't be involved.

Apart from that, it's not inconceivable the rest of the 24-man Kiwis squad could still be in contention to play in the next World Cup in 2017, likely to be held in Australia and New Zealand.

The average age of the present 24-man squad is 25. It is a young side but international league is increasingly becoming a younger man's game and they are probably a couple of years away from peaking as a team.

Pritchard is the only player over 30, and even then he entered his fourth decade while away on tour, and there are 10 players aged 24 or under.

Contrast that to Australia, who have seven over 30 and another six 28 or 29. Coach Tim Sheens was mindful of the age of a number of his players when contemplating his World Cup squad this year but felt they still had another good campaign left in them.

It's hard to argue with the likes of Cameron Smith, Johnathan Thurston, Paul Gallen and Billy Slater but there is likely to be considerable change in the Australian team following this World Cup.

Olympic athletes often talk about four-year cycles and the All Blacks know to bring in fresh blood as they peak for their World Cup, also played every four years. But it's not something the Kiwis have been able to do and NZRL high performance manager Tony Iro still thinks they are some way off being able to take that sort of approach.

They took a number of young players with them on the 2011 Four Nations tour of the UK but that was more through circumstance, with a number of first-choice players unavailable.

It proved critical in the Kiwis' development, even though they had a poor campaign, and forced youngsters like Kieran Foran, Jared Waerea-Hargreaves and Issac Luke to assume more of a leading role.

The Kiwis now have quality in key positions and there is considerable optimism that Foran and Shaun Johnson, both 23, will be steering the New Zealand side around for some time.

That can only happen if they are fit and there has been a little nervousness around what they might do if one of them picked up an injury during the World Cup, particularly with Thomas Leuluai invalided out of the tournament.

The NZRL's approach isn't to target the next four years, rather put more of an emphasis on the next eight years.

That means not only putting resources into the top under-18 and under-16 talent but also giving them reasons to want to play for New Zealand.

"Once they hopped on the plane across the Tasman, they were often ignored and we hoped they would come through," Iro says. "We have to start targeting those kids now to make sure our depth is disaster-proof.

"This year we managed to get a Junior Kiwis game in. Next year we want to identify our best 16s and 18s who live in Australia. There are heaps of them. They are guys who have come through New Zealand age group teams and been picked up by clubs and sometimes you just lose track of them for one reason or another."

Often those players were lost to Australia for good, with State of Origin a significant factor. Changes to eligibility rules will improve New Zealand's chances of retaining their best talent - players now need to be resident in Australia before they turn 13 to qualify for Origin.

On the flip side, Queensland Rugby League have indicated they won't pick players who aren't eligible to play State of Origin for junior representative sides to ensure they put their resources into their own players.

Foran played for the Australian schoolboys team - although his family moved to Sydney when he was a youngster so would have qualified for NSW under the new rules - as did Benji Marshall.

"Australia have done us a bit of a favour with the change of eligibility rules," Iro says.

"All of a sudden, a lot of players will be pointed in our direction. Origin is a massive drawcard but if they haven't got that, where does their heart lie? A lot want to put on the black jumper."

The NZRL's biggest aim is to get more New Zealand-eligible players competing in the NRL. The number has grown steadily over the past decade and the Kiwis selectors first drew up a list of about 75 names they considered for the World Cup squad.

"I believe that for us to share games regularly with Australia or become the dominant force in rugby league, which we have the potential to do, we need to have 10 of the top 20 players in each position," he says. "We have that in some positions, and are getting better, but not in others.

"Things have improved since the last World Cup but, for us to become the power we want to become, it's still a fair way away.

"We are not going to solve all our problems in four years. Building depth is almost a two-World Cup cycle. We have enough players, we just have to channel them into the right areas."

The Kiwis might have a young side, but it is increasingly becoming a younger man's game.

When once props used to mature into good players in their late-20s, it could be argued the likes of Waerea-Hargreaves, Ben Matulino and Jesse Bromwich, who are all 24, are at their peak now.

The reality is they might not be as effective as they are now in four years' time or might have been surpassed by someone else.

Either way, the NZRL hope there will be plenty more capable of taking their place.