Tevita Pangai jnr takes on Benji Marshall.

Tevita Pangai jnr has set himself the goal of playing for the NSW Blues in 2019 but concedes he has to improve his durability and strengthen his troublesome hamstrings before achieving that aim.

The Tongan international, who inked a one-year extension with the Broncos on Friday, said he had not turned his back on his heritage but also wanted to honour his upbringing and the work the NSW Rugby League put into his junior development.

The 22-year-old was born in Sydney, played his junior football in Newcastle and was a member of the NSW under 18 side.

He has told NSW coach Brad Fittler he is available for the 2019 State of Origin series and was named recently in an extended Blues squad.

"I came off a high after the Rugby League World Cup and forgot all the stuff I did as a junior playing for NSW and growing up in Newcastle," Pangai said.

"I've got to get picked first and I'm working hard to do that. I am aiming for Origin but that is a long way away.

"It was just good to see how the boys prepared [in camp in Game Three last year]."

Preparing for a gruelling NRL season is what Pangai has set his sights on.

He struggled towards the end of 2018 with hamstring issues and one of the reasons he said he signed a one-year deal, like Corey Oates, was to play the house down and earn a long-term Brisbane deal.

I've got to get picked first and I'm working hard to do that

Tevita Pangai jnr on his Blues dream

"I am in a similar situation to Corey.  I just want to back myself for another 12 months. A lot of people thought I had a breakout year but I wasn't too happy and I know I can improve on last season," he said.

"Just with the hamstring stuff, I felt I couldn't play consistently so it's back to the drawing board. I have worked hard on my hamstrings in the offseason and we've got new staff who are working hard with me.

"They are a major focus, just making sure I am on the field week-in week-out and building toward the end of the season to make sure I am peaking at the right time of the year.

"Darius Boyd has been great for me. He has had hamstring issues in the past and he is passing on his knowledge and experience."

Pangai wants to play for NSW alongside good mate Matt Lodge and the pair have been working together off the field on improving their games, including with their nutrition.

"That is a big focus. Me and Matt Lodge have looked on that as an area we can improve on for 2019 and we are really working hard on our nutrition with the staff," Pangai said.

"I haven't had bread since I've been back [to training].

"[Lodge] is a diehard Blue and grew up in Penrith. It would be good if we could get a [NSW] jersey but none of this will happen if we don’t play well for the Broncos."

Pangai said it would be ideal if he and Lodge, who recently re-signed at Brisbane for two more years, could become long-term Broncos.

"He thinks we are a package deal and if he stays I'll stay. We'll see what happens but hopefully they can keep both of us," Pangai said.

"He is one of the big reasons why I stayed. We enjoy each other's company and hang out a fair bit outside of footy.

"We hold each other accountable and just want to make each other better."