For those looking to identify future trends in rugby union the IRB’s junior world championship is the place to start. Historically New Zealand have been an irresistible Under-20 force and the All Blacks consistently reap the benefit. Times are rapidly changing. If England defeat South Africa in Friday’s final in Auckland, they will have conquered the world for the second year in a row.

It is the view of England’s head coach, Nick Walshe, that his squad have made a lasting impression on the Kiwi psyche. The ill-disciplined, limited England sides of old have been replaced by smart, polite winners playing fast, skilful rugby which New Zealanders instinctively respect. “I genuinely think they are pretty worried,” says Walshe, quietly confident his young team can deliver the Eden Park victory which proved narrowly beyond Stuart Lancaster’s seniors this month.

Walshe is not alone. The positive manner in which Lancaster’s midweek side turned over the Crusaders on Tuesday has not gone unnoticed locally and England’s Under-20s have shattered a few perceptions in beating Italy, Australia, Argentina and Ireland en route to the final. Nathan Earle, the Saracens winger, is on the shortlist for the IRB junior player of the year and his club-mate Maro Itoje has been among the stand-out forwards. The age-group conveyor belt which has lately produced Joe Launchbury, Owen Farrell, George Ford, Anthony Watson and Jack Nowell is churning out fresh talent at an ever-accelerating rate.

Sooner or later, believes Walshe, New Zealand will begin to feel the consequences. “There are a lot of old players in that All Blacks team and when they’re gone, probably after the next World Cup, they’re going to have to rebuild. We’ve already rebuilt and with the amount of players we have coming through I think they are genuinely concerned. They respect us massively.”

The fact this quiet revolution is revealing itself on Kiwi soil clearly does no harm. From the outset the ambition of the Under-20 squad was not just to retain their title but to demonstrate how English rugby behaviour has been transformed from top to bottom since the dark days of the 2011 World Cup. “What I really wanted the team to do was gain the respect of the New Zealanders in their own back yard by playing good rugby and being very good ambassadors for England on and off the field,” says Walshe, who won two senior caps at scrum-half for England in Australia in 2006.

“I know there have been a couple of dodgy trips before but, with the way my boys and Stuart’s boys have behaved, I think there’s a massive respect now. The future of English rugby is really, really bright.”

A big physical Baby Boks side, led by their mature fly-half Handré Pollard, will not easily be pushed around in the final but, as they did in beating Ireland 42-15 in the semi-final, England will be happy to back their off-loading and passing game. “The way we’ve played has been similar to the New Zealanders but we’ve set out to do it our way,” says Walshe. “It’s not necessarily about throwing the ball around willy-nilly, it’s about trying to get it into the space and find the weaknesses in defences.

“Everything we do is at a really high tempo so we can try and keep the pressure on the opposition and make sure they can’t relax. We are definitely going to carry on playing that way against South Africa. If we can play at the right tempo we’ve got a good chance.”

Win or lose, Lancaster will soon have even more artillery at his disposal for the 2019 World Cup campaign, if not before. The Premiership clubs, reckons Walshe, will also benefit. “We want to develop them not just as rugby players but as individuals … we want them to go up to senior rugby and be able to perform straight away. There are so many good young players it’s difficult to pick any of them out. I honestly believe if they keep developing a lot of this team will be pushing to get into their Premiership teams next year and, from there, into the Saxons and beyond. The amount of players coming through is really exciting.”

FIVE TO WATCH

Maro Itoje Athletic second-row forward who has already made his Saracens debut. Described as “a phenomenal talent” by the Under-20 head coach Nick Walshe

Nathan Earle Strong, fast winger who has been shortlisted for the IRB junior player of the year award. Also on Saracens’ books

Billy Burns Younger brother of Freddie Burns, England’s starting No10 against the All Blacks this weekend. Also a fly-half, he has just re-signed for Gloucester

Aaron Morris Free-running full-back from Bedford Blues. Also a county-standard sprinter and fast bowler in his youth

Nick Tompkins Sidcup-born centre who has already captained England at Under-16 and Under-17 and will continue to be eligible for the U20 side next season