Jason Nightingale has been a mainstay in the New Zealand Test side since his international debut in 2008.

When it comes to player burnout, Kiwis winger Jason Nightingale seemingly doesn't know the meaning of the term. 

The New Zealand flyer will represent his country for the 21st time on Saturday night, having lined up for the Kiwis every year since pulling on the black jumper for the first time in 2008. 

Highlights: Nightingale scores again as Kiwis pip Samoa
State of play: Kiwis in the box seat for Four Nations final

Not a calendar year has gone by since in which the 28-year-old has not represented the land of the long white cloud, no matter how exhausted his body is feeling. 

"If I was burnt out, I'd probably have to say something. You can't just go in underdone or out of shape, because you've got to be honest," Nightingale says. 

"You've got to be able to give your best for your country otherwise there a lot of other people that are willing and deserving to be there if that's the sort of shape your body's in."

Players such as rookie stars Dallin Watene-Zelezniak or Sosaia Feki, perhaps, or veteran winger Manu Vatuvei. 

But Nightingale has established himself as one of Stephen Kearney's mainstays. A reliable, experienced winger who the coach can count on no matter how many games on the NRL calendar he's played. 

Such as in 2010, when the Manly-born St George Illawarra winger played a mammoth 32 games, including twin grand final and Four Nations triumphs. 

In fact, as a testament to Nightingale's longevity, he has failed to play at least 25 games in a year just twice since making his NRL debut in 2007. 

"I suppose a lot of hard work, a lot of rehab goes into that, if you keep going on tour and keep playing all season round," he explains. 

"But then also, we get a break from pre-season. We miss the first six weeks of pre-season so that does help. That's where they get a lot of their volume in and if you miss that then it can really help you recover. 

"I think we'd all love to be playing footy all year round and never have a pre-season. I suppose missing that helps, as long as you take your break to make sure that you keep up on rehab and make sure you're actively recovering.

"It's been slow and steady, but awesome to get that (20-Test) milestone on the weekend. It's something to be proud of."

The only time Nightingale was at all hesitant on choosing to play for the Kiwis was in 2008. Having yet to represent the country of his parents' birth, the second-year winger was asked by then-Dragons coach Nathan Brown if he wanted to play State of Origin. 

"I think it was 2008 when City/Country was being picked. 'Browny' came up to me and I said I always wanted to play for the Kiwis and he said, 'Well, I'll tell City that you're unavailable'," Nightingale recalled. 

"And I said, 'Yep, go and do that.' That's when I made my decision. I debuted that year and yeah, if there was ever a choice I'd be choosing New Zealand. It's a shame that we can't be involved in Origin, but there's a lot of benefits about playing for your country. I'm sure my family are happy with my decision and I am as well."

When Nightingale returns to Wollongong after the tournament, he'll return to a club without long-time teammate Brett Morris. The injured Kangaroo winger this week announced a move to Belmore, where he'll reunite with twin brother Josh. 

Morris was one of a host of players reportedly being shopped around by the Dragons, and Nightingale voiced his disappointment in the "rumblings" going on at the club. 

"I'm definitely disappointed to see it played out in the media. I think business should be business," he said. "Obviously there's a lot of public interest surrounding it, but you'd like to see it happen more in-house than how it's been played out in Sydney."

Even Nightingale's own contract has been bandied about, although the 28-year-old insisted he would be at the club next season. His current deal ends at the end of 2015. 

"I'll definitely be there in 2015, and I'm really looking forward to that. I'm off contract, and I want to stay at the club. [But] that decision is still a long way away for me. We're talking about things in 2016 and we haven't even started an off-season for 2015," he said. 

"So it's funny when it comes down to that, there are obviously some things going on. There are rumblings coming out of there, but I'd prefer to just focus on this tour initially and then figure that out once the 2015 season comes around."