The mercy killing was finally completed as South Africa’s total dominance over New Zealand was sealed early on the fourth day of the second cricket test.

South Africa’s pacemen broke down the stubborn resistance of BJ Watling (63) and Dean Brownlie (53), then ripped through the New Zealand tail with the second new ball to complete an innings and 193-run victory.

The tourists were dismissed for 211 off 86.4 overs in their second innings, with the last rites read 35 minutes before lunch at a windswept St George’s Park.

It completed a one-sided 2-0 series win for the world’s undisputed No 1 test side and highlighted the gulf between their lofty perch, and the world no 8 New Zealand team who’ve now lost six of their last seven tests.

A 167-run win over Sri Lanka in Colombo, in Ross Taylor’s final test as skipper in November, shines like a beacon.

South Africa had three centurions in their 525-8 declared, Hashim Amla, Faf du Plessis and Dean Elgar, then the world’s No 1 test bowler Dale Steyn took 8-65 for the match.

New Zealand’s two best batsmen of the series, Watling and Brownlie, began the day on 157-4 facing a huge task, 247 runs behind and two days to save the test.

Both looked comfortable enough, dispatched the bad deliveries and each raised their half-centuries as the South Africans operated with spinner Robin Peterson and killed time till the second new ball.

Watling reached his second 50 of the match, off 92 balls, and Newlands centurymaker Brownlie got there soon afterwards off a more circumspect 129 deliveries.

The pair were two short of a century partnership for the fifth wicket before Brownlie lost concentration against Jacques Kallis who has the knack as a partnership-breaker.

With assistance from the gusty wind, Kallis got one to swing away and Brownlie followed it, touching an edge. His 53 spanned 175 minutes but the end looked nigh for his team.

Debutant Colin Munro survived a pair with a short single off Peterson but didn’t look comfortable against spin. So he attacked, advancing on Peterson for consecutive boundaries.

At that stage the only people on the field not born in South Africa were the two umpires.

The Durban-born pair were then faced with the second new ball, which home skipper Graeme Smith took after 81 overs.

It didn’t take long to do the trick, with Munro (15) removed from the fifth ball by Morne Morkel. Bowling around the wicket, he got one to bounce and Munro edged to the cordon.

Steyn, who took his 19th bag of five wickets in the first innings, then fired up to finish the job.

He bowled Watling with a snorter that nipped away and clipped off stump, ending the brave resistance of the wicketkeeper who batted a tick over five hours in the test for 63 in both knocks.

Doug Bracewell and the promoted Trent Boult weren’t there long, then Steyn finished it when Neil Wagner attempted a hook shot and was caught behind.

The team reconvene for the first of three one-day internationals in Paarl on Saturday.

SCOREBOARD on the fourth day of the second cricket test at St George’s Park:

SOUTH AFRICA

First innings 525-8 dec

NEW ZEALAND

First innings 121
Second innings (157-4 overnight)

M Guptill b Kleinveldt 48

B McCullum lbw b Peterson 11

K Williamson b Peterson 11

D Brownlie c de Villiers b Kallis 53

D Flynn c de Villiers b Kleinveldt 0

B Watling b Steyn 63

C Munro c Petersen b Morkel 15

D Bracewell c Petersen b Steyn 0

N Wagner c de Villiers b Steyn 4

T Boult c Peterson b Morkel 3

J Patel not out 0

Extras (lb 2, wd 1) 3

Total (86.4 overs) 211

Fall: 1-40 (McCullum), 2-64 (Williamson), 3-84 (Guptill), 4-84 (Flynn), 5-182 (Brownlie), 6-203 (Munro), 7-203 (Watling), 8-204 (Bracewell), 9-207 (Boult), 10-211 (Wagner).

Bowling: D Steyn 15.4-2-48-3, M Morkel 16-6-36-2 (1w), R Kleinveldt 15-8-44-2, R Peterson 26-13-47-2, J Kallis 9-3-18-1, G Smith 1-0-10-0, A Petersen 4-0-6-0.

Result: South Africa won by an innings and 193 runs, won two-test series 2-0.

- © Fairfax NZ News