Tim Sheens has assembled the third-oldest Kangaroos side in history for Friday night's Anzac Test at Suncorp Stadium, while New Zealand will bank on a much younger core group as they try to make it three wins from as many games against their trans-Tasman rivals.

Already veteran lock Corey Parker (33) has suggested this could be his final outing in the green and gold, given it's the only match for the Kangaroos in 2015. Smith (31), Johnathan Thurston (32), the injured Billy Slater (31) and Cooper Cronk (31) have been a constant for Australia but the winds of change may not be far away.

Next year's Test stands to present a dilemma for selectors as they try to refresh the ranks. But Smith has urged powerbrokers to resist change for the sake of change and to pick players on merit, regardless of how long they have left in the game.

The stature of a number of the senior members of the side, considered to be among the greats of the game, adds layers of delicacy to any deliberate attempts at restructure. As does the form of late bloomers such as Parker, who Smith said was playing as well as ever at the back of the Broncos scrum.

"The day is going to come when a few of our older boys are going to leave the Australian side. There's no doubt about that. We can't go on forever. We'd all love to but that's not going to happen," Smith said.

"Corey might be very modest there, too. I think he's playing the best football of his career at 33."

Smith said there was a clear desire from senior players to campaign for as long as possible, although Justin Hodges would be the first to call time on his representative career on the weekend, only to be overlooked by Sheens as he sought a final outing for his country.

"I just think, for myself and a lot of the other boys, age is not a factor. If you're playing good football and deserve to be picked in representative teams, you should be there," Smith said.

"There's no doubt you have a few guys around the 30 mark. But you look at those guys and they're playing well. Everyone is saying Johnathan Thurston is the best player in the game at the moment. He's 32.

"Really, age doesn't come into consideration. When it comes to selection, if you're playing well, you should be there."

Another loss to New Zealand would pave the way for the Kiwis to claim the world No.1 ranking but both New Zealand captain Simon Mannering and coach Stephen Kearney said that wasn't on their radar, despite the good it may do for the code in the rugby-mad nation.

"I guess [it's] not so much ranked the top nation, more just to bring success to the Kiwi jersey. Any time we play well, it improves the profile of rugby league in New Zealand. It is dominated by rugby union," Mannering said.

And Kearney said: "From our point of view, that [being No.1] doesn't really come into the equation. It doesn't even enter into our psyche. It's a non-issue for us."

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