South Africa treated New Zealand to a lesson in batting application on a disrupted second day of the third test in Wellington. The Proteas were 246 for two at stumps. Alviro Petersen (96) and J-P Duminy (76) starred on a day which lasted just 37 overs, produced 110 runs and offered no wickets. They performed in front of a hardy group of cricketing faithful, some of whom were exposed to a formidable northerly gale. Fine weather is forecast over the next three days. The efforts of Petersen, who is closing on his third test century, and Duminy, who is playing his first test in more than two years, were exceptional in their unbeaten 140-run partnership. Both were particularly strong off their pads and in the cover region. The only chance in the day came from the bat of Petersen. He edged a Doug Bracewell delivery to third slip on 68, only for it to be dropped by Martin Guptill. The efforts of the South African duo were underlined by the depth they gave their side\'s batting in the absence of Hashim Amla and Jacques Kallis. Kallis suffered a stiff neck and was replaced by Duminy just before the match. Amla underwent emergency surgery after suffering a groin injury from a Chris Martin delivery yesterday. Amla was on 33 when he slumped to the ground but batted a further 12 and a half overs to make 63. \"Hashim underwent emergency exploratory surgery resulting from blunt trauma sustained to his groin region,\" South African team manager Dr Mohammed Moosajee said. \"He spent the night in hospital and was discharged this morning. The surgeon is satisfied with the outcome and expects Hashim to make a full recovery. However, it is unlikely he will take any further part in the current test.\" New Zealand\'s Daniel Vettori said it was difficult for bowlers to settle in the conditions. \"Into the wind it was tough getting blown around in your run-up and delivery stride. Even for the fast bowlers coming down wind took some adjustment. Vettori was impressed with the South African batsmen. \"Petersen read the situation well. He had Amla and Duminy attacking at the other end and was able to stick it out and bat as long as possible.\" Duminy said he felt comfortable playing the short ball - one of his previous weaknesses. He said facing bowlers into the wind posed the biggest problem. \"When they pitched up the ball started wobbling a bit so you had to play as straight as possible.\"