Before he became the Blues newest enforcer and the latest NSW player to assume the mantle of public enemy No.1 in Queensland, David Klemmer was a teenage halfback playing in the lower divisions of the local Parramatta competition.

In fact, the biggest – and youngest – player on the field in Wednesday night's Origin decider may never have got his chance in the NRL if his schoolboys coach at Westfields Sports High, Wayne Lambkin, hadn't convinced him that his future lay at prop before he was spotted by former Canterbury recruitment manager Peter Mulholland as a 15-year-old.

It has been a remarkable rise since then for Klemmer, who did not start an NRL match until round nine this season and has done so just twice in 37 appearances for the Bulldogs, four Tests for Australia and two Origins in the sky blue jersey, according to Champion Data.

After earning the wrath of Maroons veteran Corey Parker and cult hero status in NSW with his 24-minute impersonation of a raging bull in Origin II at the MCG, Blues officials have tried to shield the 21-year-old giant from the spotlight in the lead up to the decider at Suncorp Stadium.

But while they may be uncertain how Klemmer will cope with playing in the most hostile environment of his short career, those who know the 200-centimetre, 120-kilogram front-rower believe it is just another step in what is destined to be a long and successful career.

"He is doing something right if he is not liked in Queensland," Canterbury captain James Graham said. "Klemmer is not going to bat an eyelid at that, I don't think he really cares to be honest.

"He has been really impressive this year. I think we saw glimpses of it last year but this year he has been outstanding and I know some people may have been critical of his aggressive nature, but I don't think that is a bad thing at all.

"He is definitely someone you want on your team and the thing that impresses me the most is that, when he was younger, you could see he was big, you could see he had ability but what he has managed to do is marry that talent in with hard work and work ethic, and I think that is what makes him one of the best young forwards this country has ever seen."

Former Blues prop Jason Ryles, who also played halfback in his junior days, is another to sing Klemmer's praises after being on the coaching staff of the 2013 NSW under 20s team, of which Klemmer was captain.

Ryles said Klemmer had natural leadership qualities and he admired the way he had stood up to the Maroons forwards.

"I know exactly how he feels in those situations, you just get fired up," Ryles said. "I love his work and I love what he is doing.

"I think he has brought a bit of life back into Origin from a NSW point of view. It is just raw-boned aggression and I think it is really good we have got these kids like him and Aaron Woods coming through. They don't take any crap off the older guys they are playing against and aren't worried about reputations. I think it is good for NSW and good for Origin."

The thing that impressed Mulholland about the then 15-year-old was "his size 17 boots", while Lambkin also said the first thing he noticed when Klemmer started high school at 12 years old was "how incredibly big he was". But they insist that there is more to him than just size and aggression.

"He was a fun kid at school, he was liked by everybody, like he is at the moment," Lambkin said. "I don't know that he concentrated too hard on the school work, but he never got into much trouble and he made his way through to Year 12. He married a girl from school and they have got a couple of kids.

"Even when he was young, he was always big and he was always destined for something. He was only playing lower divisions in the Parramatta district competition and he had a few things going on.

"He was playing halfback and his dad was the coach, but we said to him, 'What are you doing? You are going to be a front-rower. Get yourself in a decent footy team in a decent competition, play front row and forget about all of the other stuff'.

"He had really nice skills as well as the size; he could catch and pass and, at the end of the day, without those, you are most probably just a big battering ram and you last for only so long."

Mulholland spotted Klemmer playing for All Saints Toongabbie and had no trouble convincing him to play for Canterbury.

"He just couldn't make the Parramatta rep sides so I invited him over and he was a Bulldogs supporter ... so it was an easy sell," he said.

According to Canterbury and NSW teammate Brett Morris, Klemmer trains the way he plays.

"There were a couple of times at training in the off-season when he took my head off," Morris said. "He is passionate, he loves his job and gets out there and rips in. We are lucky we have him at the Bulldogs and the Blues. We don't want him to change."

Five Things You Didn't Know About David Klemmer

1. He used to play halfback as a junior for All Saints Toongabbie

2. He was recruited to Canterbury from the fourth division of the Parramatta Under 15s competition.

3. He met his wife at school and they have two children.

4. His childhood heroes were Mark O'Meley and Willie Mason, and he had a Bulldogs doona cover on his bed.

5. He also showed promise at Aussie rules, softball and shotput but always wanted to play in the NRL.