South Africa captain Graeme Smith decided against practising on Monday as he attempted to shake off an illness in time for the second one-day international against New Zealand on Tuesday.
Team coach Eric Simons described Smith as "a bit bunged up", saying he had suffered a cold over the last two days and the infection had gone to his chest.
"He's on antibiotics. He's feeling a little bit stronger and I'm sure he'll be fine for the match tomorrow," Simons told reporters.
Smith led South Africa to a five-wicket victory in the first game of the six-match series in Auckland on Friday.
Simons said New Zealand played much as his team had expected in Auckland where South Africa reached their 226-run target with two balls remaining.
"They (New Zealand) are a side that don't panic. They play clever cricket and they know how to go about their jobs," said Simons.
DIFFICULT WICKET
{{/usCountry}}DIFFICULT WICKET
{{/usCountry}}"The wicket was difficult for both sides to bat on but I think New Zealand posted a decent score in those conditions.
"Their depth of batting is a great asset and (captain) Stephen Fleming is very innovative in his thinking and very attacking. He doesn't allow you much freedom."
Simons said he was disappointed South Africa missed a number of possible run-outs.
"Run-outs are so important and we could have hit the wicket a few more times, which might have made a difference. We've done a bit of work on that today," he said.
"We also allowed ourselves to be put under pressure in the middle of the innings last time when we lost a couple of quick wickets. We had a buffer in our favour and we almost let that get away.
"We don't want to go into the last over when for a while we were doing it quite easily. It was pretty nerve-wracking on Friday."
Simons said if Smith was fit, South Africa would probably go into Tuesday's match with the same 11 who have played the last six one-dayers.
New Zealand (from): Stephen Fleming (captain), Michael Papps, Hamish Marshall, Scott Styris, Craig McMillan, Chris Cairns, Jacob Oram, Brendon McCullum, Kyle Mills, Daniel Vettori, Daryl Tuffey, Michael Mason.
South Africa (from): Graeme Smith (captain), Herschelle Gibbs, Jacques Kallis, Boeta Dippenaar, Jacques Rudolph, Mark Boucher, Shaun Pollock, Lance Klusener, Robin Peterson, Makhaya Ntini, Andre Nel, Nicky Boje.