Gibbs, back from injury, said he expected good performances from the five South Africans who played for the unsuccessful World XI one-day and Test teams against Australia.
He said: "I think that the guys who went to the Super Series will want to do well because they have a point to prove. I think their reputations took a bit of a knock."
South Africa started their preparations for Friday's match without captain Graeme Smith, wicketkeeper Mark Boucher and all-rounders Jacques Kallis and Shaun Pollock, who were due to arrive back from Australia.
Fast bowler Makhaya Ntini, who played in the Super Series one-day games, returned earlier.
Gibbs said new coach Mickey Arthur had suggested he might open the batting after a stint in the middle order last season. "I'll be happy to move back up the order. Some of my best cricket has been as an opener. I won't necessarily open, but I would like to be in the top three."
But it will be a gamble for South Africa if Gibbs opens Friday in a form of the game which does not allow much time for a batsman to settle in. A knee injury kept Gibbs out of the Afro-Asia Cup in August and forced him to withdraw from the World XI one-day team.
He admitted that he was short of match practice but said he had felt in good form in net practices with the Cape Cobras franchise team and in individual sessions with national high performance manager Gary Kirsten.
While it will be South Africa's first 20-overs international, most of the team have played the shortened game in domestic cricket, while South Africa were comfortable winners in a one-day international in the West Indies last season which was reduced by rain to 20 overs a side.
New Zealand will provide stern opposition, however, after starting their tour with two convincing wins over South Africa A.
Skipper Stephen Fleming and Craig McMillan hit centuries in the warm-up games, while fast bowler Shane Bond was in excellent form.
The 20-overs match will be a pipe-opener for a series of five conventional 50-overs internationals starting in Bloemfontein Sunday.
United Cricket Board chief executive Gerald Majola said that despite the popularity of domestic 20-overs games, his board believed they should be restricted to "one-offs" at international level.
"We don't believe they should be part of the International Cricket Council calendar but should be kept as a domestic product. In our case, it is the only domestic competition that generates income for the franchises."
New Zealand's only previous 20-overs international was against Australia in Auckland in February, when Ricky Ponting's unbeaten 98 off 55 balls inspired Australia to a 44-run win.
On that occasion, the New Zealand team wore beige kit from the 1980s and some of the players sported unusual hairstyles. This time, though, they will be turning out in their regular black uniforms and treating the game as a no-frills international contest.
New Zealand won their most recent one-day series against South Africa by five matches to one in New Zealand last year but South Africa have generally held the advantage when they have played the Kiwis at home.
A notable exception was New Zealand's upset win at the Wanderers during the 2003 World Cup, a result which contributed to South Africa's early exit from the tournament.
South Africa: Graeme Smith (captain), Jacques Kallis (vice-captain), Nicky Boje, Mark Boucher, AB de Villiers, Boeta Dippenaar, Herschelle Gibbs, Andrew Hall, Justin Kemp, Charl Langeveldt, Albie Morkel, Andre Nel, Makhaya Ntini, Shaun Pollock, Ashwell Prince. Coach, Mickey Arthur.
New Zealand: Stephen Fleming (captain), Daniel Vettori (vice-captain), Andre Adams, Nathan Astle, Shane Bond, James Franklin, Hamish Marshall, James Marshall, Brendon McCullum, Craig McMillan, Kyle Mills, Jacob Oram, Jeetan Patel, Scott Styris, Lou Vincent. Coach, John Bracewell.