Hamilton: Kane Williamson posted his 17th test century and Jeet Raval his highest test score on a day of milestones and faint controversy over South Africa's treatment of the ball in the third Test between New Zealand and South Africa.
Williamson matched Martin Crowe's record for the most test centuries by a New Zealander and became the sixth Kiwi to pass 5,000 runs in tests during a 190-run partnership with Raval (88) which was the highest for New Zealand's second wicket against South Africa.
The stand, which occupied most of the third day, helped New Zealand reach 321-4 in reply to South Africa's first innings of 314, a lead of 7 runs by stumps, with Williamson 148 not out and Mitchell Santner 13.
South Africa fought back with a flurry of wickets near the close, dismissing Neil Broom (12) and Henry Nicholls (12) as New Zealand dipped from 273/1 to 293/4 but Williamson and Santner saw the home side to stumps in gloomy conditions.
Only four wickets fell in the 79 overs bowled on the third day. Two belonged to paceman Morne Morkel, who became the sixth South African to take 250 wickets in tests. He achieved the milestone with his first wicket of the day in Tom Latham (50), who ended a lengthy form slump with his 13th half century in an 83-run first wicket partnership with Raval.
Morkel dismissed Raval 68 overs later when New Zealand, who had been 83/1 on Latham's departure, was 273-2 and in a powerful position in the match. He joined Shaun Pollock (421), Dale Steyn (417), Makhaya Ntini (390), Allan Donald (330) and Jacques Kallis (291) among South Africans with 250 wickets.
In passing 60, with a six off Vernon Philander which took his score from 57 to 63, Williamson became the sixth New Zealand to pass 5,000 runs in tests after Stephen Fleming (7,172), Brendon McCullum (6,453), Ross Taylor (6,030), Crowe (5,444) and John Wright (5,334).
Controversy came midway through the day, soon after the ball had begun to reverse swing, when Australian umpires Rod Tucker and Bruce Oxenford ordered the ball to be changed, apparently because of their concern the fielding side had deliberately affected its condition.
The South Africans appeared to intentionally throw it to the keeper on the bounce -- usually on the pitch -- with a side-arm action ostensibly aiming to always land it on the same side. Causing one side to become scuffed aids the pursuit of reverse swing.
After examining the ball, Tucker and Oxenford called for a replacement. A long conversation followed between the umpires and Proteas captain Faf du Plessis, who appeared to argue that the ball should not be changed, presumably because its deterioration was natural, and thus a fair advantage to the bowling team.
South Africa then seemed resentful of the forced change. Du Plessis approached the umpires twice to suggest the replacement ball had gone out of shape and swing bowler Vernon Philander, most affected by the ball change, resorted to rolling the ball back from the outfield in an act of protest.
No charges had been laid by the end of play and it is not uncommon for bowling sides to use methods similar to those used by South Africa Monday to advance the ball's deterioration and to aid reverse swing.
But the incident was the second controversy involving South Africa and the ball this southern season. Last November, du Plessis was found guilty of ball tampering during a test against Australia in Hobart, after being caught on camera applying saliva to the ball with a mint in his mouth. He was fined his full match fee and given three demerit points.
Nothing on Monday detracted from Williamson's record-equaling century, his second of the series after his 130 in the first test at Dunedin. By stumps he had batted for five-and-a-half hours and struck 14 fours and three sixes.
Raval fell short of his maiden test century but beat his previous test-best of 80 in an innings which occupied six-and-a-half-hours.
Santner survived being bowled by Philander off a no ball when he was 4 to help New Zealand reach stumps after the sudden loss of two late wickets.
"It was a perfect day for us to be ahead of them now and only four down," Latham said. "The top order did a lot of hard work.
"That partnership between Kane and Jeet after I was out was pretty key and for them to put on just under 200 was outstanding."