Chris Cairns will be the one who decides if he is fit enough to play in tomorrow's vital VB Series match between New Zealand and South Africa at Perth, according to Stephen Fleming. "It will be his call again," said Fleming. "He knows his body very well." But he was not overly optimistic. "I am very cautious about Chris's chances, because this is not just about his bowling," Fleming said. "It's his batting and even running that is causing the pain. We won't put him at any risk."

Cairns's back injury prevented him from bowling in the last match, against Australia on Tuesday, although he was able to biff a typically belligerent 55 and is now the leading run-maker in the competition, with 257. But New Zealand know they are at their best when Cairns can operate in true allrounder mode.

Fleming said: "He is important with his experience and variations and without his bowling services there has to be a gap filled. It will be fantastic when he's back to full fitness, it gives us a very well-balanced side."

New Zealand are also waiting on the fitness of Daniel Vettori, who suffered whiplash and mild concussion after falling in a failed attempt to take an outfield catch on Tuesday. Vettori was unable to take part in today's practice session, but a precautionary brain scan has ruled out any damage. Their woes are completed by doubts over allrounder Scott Styris, who has an injured foot.

The South Africans have no such concerns, and Shaun Pollock is confident that Allan Donald will rise to the occasion. "Allan has quite a bit of cricket under his belt now," Pollock said. "He's firing on all cylinders and raring to go. I'm sure you'll see a fine performance from him."

"We would ideally like to have qualified after Friday's game," Pollock added. "But that's not our main aim. Our main aim is going out there and making sure we win it, then we can wait and see what Sunday entails for us."

Possible permutations from the two remaining qualifying matches abound (click here for full details) but life is relatively simple for New Zealand. A win tomorrow would guarantee their place in the final of a tournament in which many had assumed they would come a humble third. South Africa are also in control of their own destiny.

As the tournament goes to the wire, gripes about the schedule have resurfaced. New Zealand, after a six-day lay-off earlier in the series, are now facing their fourth match in seven days, a situation that hasn't helped players trying to shake off niggles.

Denis Aberhart, New Zealand's coach, said: "We've come from Sydney to Bowral to Sydney to Adelaide to Melbourne to Perth in a week, and we've had four games of cricket in that time. We're just going to have to bounce back and it's a matter of us fronting up."

In contrast South Africa have just had a five-day break and a longer opportunity to practise on the bouncy WACA pitch. "It's an advantage to us," said Pollock. "We can get used to the conditions here and get over any niggles. We've got games on Friday and on Sunday now so it will be a tough weekend. It was a good time to have a break now."

New Zealand (probable) 1 Brendon McCullum, 2 Nathan Astle, 3 Lou Vincent, 4 Stephen Fleming (capt), 5 Craig McMillan, 6 Chris Cairns, 7 Chris Harris, 8 Adam Parore (wk), 9 Daniel Vettori, 10 James Franklin, 11 Shane Bond.

South Africa (probable) 1 Herschelle Gibbs, 2 Gary Kirsten, 3 Jacques Kallis, 4 Neil McKenzie, 5 Jonty Rhodes, 6 Mark Boucher (wk), 7 Shaun Pollock (capt), 8 Nicky Boje, 9 Justin Ontong, 10 Allan Donald, 11 Makhaya Ntini.

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