Daniel Vettori bowled 42 wicketless overs in South Africa's first innings of the third test as his poor series against the Proteas continued, but Alviro Petersen says the campion spinner is far from done. Vettori, playing his 111th test, was forced in to producing plenty of donkey work with his left-arm orthodox deliveries in to a stiff northerly wind at the Basin Reserve in Wellington today as South Africa racked up 474-9 declared in their first dig. That aside, the 33-year-old rarely threatened the Proteas, although, Petersen, who made a career-best 156 for the visitors, said they just tried to nullify Vettori rather than attack him. "He is a world-class bowler," Petersen said. "His main role is to try and tie up an end. From our point of view, we don't want to give him wickets, because we know he is a big bowler for them. We didn't want to give him wickets and we tried to score off any bad balls that he bowled. He doesn't bowl a lot [of bad balls] but the ones that come we try and score off." Petersen said the pitch did no favours for Vettori.A few did turn but I don't think the wicket is a turning wicket. He is a wily old customer, who tries bowl straight, tries to get you lbw and if you can combat that you will be fine." Heading in to the third five-day contest, Vettori had only claimed two wickets for 147 runs from the first two tests, which are hardly ideal figures from your front-line spin bowler. The long-time fixture of New Zealand's side in all forms of the game has stepped away from limited overs cricket recently to focus on his test performances but it doesn't appear to have paid dividends. Since the beginning of 2009, Vettori has played 22 tests - including the ongoing one against South Africa - and picked up 72 wickets at an average of 38.33, down on his career bowling mark of 34.14. During the past three and a bit years his strike rate of balls bowled per wicket has blown out to 93.5, while his career mark stands at 79. While New Zealand's seaming wickets don't tend to favour spin bowling it's a worrying trend for Vettori and New Zealand coach John Wright. The Kiwis have a heavy diet of test cricket awaiting them during the next 12 months and the side will be hoping their wise left-armer can break out of this slump.