Seddon Park, Hamilton Photo: Andrew Cornaga/www.photosport.nz
New Zealand need 227 more runs to win the second cricket test and record their first ever series win over South Africa.
An understrength South Africa need nine wickets to cause an upset.
At stumps on day three in Hamilton the Black Caps are 40-1 chasing 267 for the win.
Devon Conway's run of lean results continued when he was out for 17 just before the end of the day's play.
Earlier, South Africa had the upper hand for most of the day before losing their last five wickets for just 22 runs.
Starting the day with a 31 run lead the visitors were 88-3 at lunch in their second innings with Will O'Rourke taking two wickets and Rachin Ravindra one.
By tea South Africa had fought back to be 186-4 thanks to a steadying fifth wicket partnership between David Bedingham and Keegan Petersen.
Bedingham brought up his highest test score of 110 off 141 balls including 12 fours and 2 sixes before becoming O'Rourke's third wicket of the innings.
Petersen's 43 was the second highest score of the South Africa innings.
O'Rourke and Glenn Phillips combined to rip through the Proteas' lower order and give New Zealand a chance to chase down a total of 267 for victory.
O'Rourke finished with 5-34 to take his first five wicket haul in test cricket
The Black Caps will start day four on Friday with Tom Latham on 21 with Kane Williamson set to join him.
New Zealand lead the two test series one nil.