New Zealand will go into this week's one-day cricket finals series as the surprise packet of the tournament, but carrying a fatal flaw.

The Kiwis' inability to control the opposition scoring in the last 10 overs looms as the difference between them and South Africa from tomorrow at the MCG.

The likely returns of allrounder Chris Cairns (back) and Shane Bond (groin) will boost the Black Caps at the MCG tomorrow on Waitangi Day, their national commemoration, for game one of the best-of-three finals series.

But they are still trying to work out tactics for the most crucial period in the one-day match.

"We've seen teams become very good at exposing bowling in the last 10 overs - we saw a case of it the other day with Australia beating South Africa, so it's not easy," said Kiwi captain Stephen Fleming.

"It's just repetition - getting the options right, discussing the options.

"It comes down to accuracy in those last 10 overs and all the best plans depend on the accuracy of the bowler - it is a tough skill."

Cairns and Bond would be the first choices to bowl at the end of the innings, but Cairns' bowling availabilty remains in doubt.

He did some bowling in the nets today and New Zealand will leave it until just before the start of the match to decide his role.

Cairns did not bowl in the loss to Australia last week when Michael Bevan's century turned the match around in the late overs, and he then missed last Friday's loss to South Africa altogether.

"If he's 100 per cent fit, he's a genuine option (to bowl at the end of the innings), he has been at the start of the tournament," Fleming said.

"It's whether firstly if he's fit enough to bowl, secondly if he's fit enough to come back, thirdly if he's able to bowl a third spell at the death - a lot of question marks on that.

"At full fitness he's the guy who wants it."

Australia was the title favourite at the start of this series, but New Zealand deserved its finals berth after some impressive wins, particularly in early games.

South Africa and New Zealand are yet to win this series.

The Kiwis have also beaten South Africa only once in their last 16 one-dayers, something Fleming was coy about.

"There's a couple (of reasons) and I don't want to talk about it," he said.

South African captain Shaun Pollock said little could be read into the form between the two sides on the eve of the finals.

"We have played well against them, but at finals time that counts for nothing," he said.

"What you bring into the finals from the rest of the series means nothing."

While South Africa will go into the finals with a settled line-up, Pollock said "one or two" changes might be made.

Possible line-ups:

South Africa: Shaun Pollock (capt), Nicky Boje, Mark Boucher, Boeta Dippenaar, Allan Donald, Hershelle Gibbs, Jacques Kallis, Justin Kemp, Gary Kirsten, Neil McKenzie, Makhaya Ntini, Jonty Rhodes (12th man to be named).

New Zealand: Stephen Fleming (capt), Andre Adams, Nathan Astle, Shane Bond, Chris Cairns, James Franklin, Chris Harris, Craig McMillan, Dion Nash, Adam Parore, Daniel Vettori, Lou Vincent (12th man to be named).

© 2002 AAP