DUNEDIN: Opener Dean Elgar produced an immense effort of concentration to make 89 as South Africa, reaching 224-6, built a 191-run lead after the fourth day of the first cricket test which New Zealand made tense with three late wickets. After achieving his highest test score of 140 in just less than seven hours in South Africa's first innings of 308 — later surpassed by New Zealand's 341 — Elgar batted six hours in cold, dark and difficult conditions Saturday to thwart the home side. Over those two innings Elgar occupied the University Oval crease for 13 hours, coping with a pitch which was slow and low on the first day and which had become worn and treacherous when he batted through most of the fourth day before falling close to stumps. The left-hander seemed set to become the seventh South African to score centuries in both innings of a test before making an uncharacteristic error inside the last hour, scooping a catch from the bowling of off-spinner Jeetan Patel to New Zealand captain Kane Williamson. Patel featured in New Zealand's late rally, dismissing Elgar, then bowling Quinton de Kock (4) while fellow spinner Mitchell Santner bowled Temba Bavuma (6) to keep the match closely poised. Captain Faf du Plessis achieved his 11th test half-century and ended the day 56 not out, while Vernon Philander nervously made his way to 1 from 12 balls by stumps. Trailing on the first innings by 33 runs, South Africa began the fourth day at 38-1, with a lead of only five runs. Hashim Amla fell during the morning session for 24, leaving the Proteas 39-2 — effectively 6-2 in their second innings and in danger of starting this three-match series with defeat. It was then that Elgar's iron will was most clearly on display. He added 74 in an eventful partnership with J.P. Duminy, then 80 for the fourth wicket with du Plessis, who was still at the crease when bad light ended play at 6.30pm. The elongated and disrupted day tested both teams. Play began 30 minutes late because of morning showers and players had been on the field only 20 minutes when forced off through bad light. They were absent only 10 minutes before the light improved and for the remainder of the day the battle was more against the bitter cold than light or rain. South African-born seamer Neil Wagner shouldered a heavy burden for New Zealand, bowling 27 overs and taking 2-57 while 36-year-old off spinner Jeetan Patel bowled 36 overs and took 2-72. Elgar took 228 minutes and 144 balls to reach his sixth test half-century, after completing his seventh century on Thursday. Duminy's innings of 39 highlighted the many chances New Zealand squandered on Saturday. He was spared on 2 when New Zealand wastefully challenged a caught-behind refusal off Trent Boult's bowling. On 20, New Zealand opted against a review, though replays showed Duminy would have been out lbw to Patel. He was then hit on the pads and New Zealand did review, unaware the ball had taken a thick edge. Duminy's luck finally ran out on 39 when Wagner hit his pads, he was given out, and his own call for a review was unsuccessful. Patel then dismissed de Kock for the second time in the match. Bavuma was bowled by Santer, pushing well forward to a ball which spun under his bat and hit off stump. 'We're in with a chance if we can do something similar tomorrow morning, try to eke out a few wickets then chase a score,' Santer said. 'The key thing is we didn't let them get away and that's what we've got to do tomorrow as well.'