A heroic century by 21-year-old Kane Williamson trumped a hostile South African bowling attack and allowed New Zealand to hang on for a tenacious draw in the third Test on Tuesday. South Africa secured the series 1-0 but were on the verge a second victory before tea after a sensational bowling performance by Morne Morkel reduced New Zealand to 83-5. In a dramatic final session, New Zealand lost only one further wicket as Williamson held firm in a defiant 80-run stand for the sixth wicket with Kruger van Wyk, following that with an unbeaten 37-run partnership with Doug Bracewell. The South African fieldsmen grounded multiple chances helping New Zealand reach 200-6 at the close after South African captain Graeme Smith set an imposing 389-run target. Morkel ripped out the New Zealand top order to finish with career best figures of six for 23 which won him the man-of-the-match award over Williamson. But Morkel and fellow quicks Morne Steyn, Vernon Philander and Marchant de Lange had reason to believe they could have cleaned out New Zealand had the fielding been sharper.