South Africa's Morne Morkel ducks a bouncer from New Zealand's Chris Martin during their first international Test match of the series in Dunedin.

Dunedin - New Zealand battled their way to 40 for one at lunch on the second day of the first Test against South Africa on Thursday after they had bowled the visitors out for a modest 238 midway through the first session at University Oval in Dunedin.

Martin Guptill was on 16 while Brendon McCullum was on 18 at the break. Rob Nicol was dismissed for six when he was caught by Graeme Smith at first slip off the bowling of Vernon Philander.

The South African pace trio of Dale Steyn, Philander and Morne Morkel had been impressive in the hour they bowled to New Zealand's batsmen with a testing line and length despite not getting much from the wicket.

The visitors had resumed on 191 for seven with Jacques Rudolph on 46 while Philander was on four.

The pair compiled a 35-run partnership that had become a nuisance to the home side before Philander slashed at a short wide delivery from Chris Martin and was well caught in the gully by Kane Williamson for 22.

Rudolph, who had just brought up his 10th test half century, then holed out to backward point when he failed to get over the top of a full delivery from Doug Bracewell and was caught by Trent Boult for 52 in the next over.

Imran Tahir was the last South African wicket to fall, run out for 10 while attempting a third run on a shot to the boundary that was well fielded by Daniel Vettori.

Martin had grabbed three wickets in four balls after tea on the first day as the hosts took six wickets for 105 runs in the final session.

If South Africa sweep the series 3-0, they will take over the world number one test ranking from England. - Reuters