
Sonny Bill Williams takes a selfie with fans during the cup final against South Africa at the Wellington Sevens.

Williams celebrated his debut in the sevens format as the All Blacks won the tournament for the third year in a row to get off the mark in this season's World Series.

South Africa, which won the previous round in Cape Town in December, rocked the home side from the start and took a 14-0 lead through tries to captain Philip Snyman and Rosko Specman (here tackling Gillies Kaka).

Akira Ioane, once heralded as "the next Jonah Lomu," kept New Zealand in the game with a touchdown of his own and superb try-saving tackle.

An error by 2015 Rugby World Cup winner Williams allowed fellow 15-a-side convert Francois Hougaard to set up Seabelo Senatla for South Africa's third try.

With Specman in the sin bin, Ioane's teenage brother Rieko took advantage to cross the line twice as the All Blacks closed to two points.

Joe Webber then scored a dramatic last-gasp winner after sterling defensive work at the other end of the pitch by teammate Regan Ware, for a final score of 24-21 against the Sevens World Series leader.

Williams made a strong debut on Saturday as New Zealand won all three group games, and also scored a try in the 25-5 semifinal win over England. The All Blacks thrashed Kenya 36-0 in Sunday's opening quarterfinal.