Martin Guptill, who had battled a hamstring strain returns for Brownlie, however he won't play the warmup match against the tourists at Eden Park on Tuesday as a precaution.
Legspinner Ish Sodhi retains his place alongside Mitchell Santner, offering two frontline spinners if required.
''That gives us flexibility and Ish is an aggressive bowler who in the right conditions can be a real threat for us," Larsen said.
The T20 squad for the sole shortest form game on Friday night. has big-hitting Corey Anderson back, while Tom Bruce retains his spot, after his 81-ball century for Central Districts in their playoff win over Northern Districts in the Ford Trophy yesterday.
As expected there is no place for veteran Ross Taylor in the T20 makeup.
However Taylor is playing in the warmup tour game on Tuesday, primarily to give him a look at the South African bowlers ahead of the ODI series and tests.
CD left armer Ben Wheeler gets a chance to build on his two matches against Bangladesh at Mt Maunganui.
The selection for Tuesday's game contains some of the country's bright young prospects, including Auckland batsmen Glenn Phillips and Mark Chapman, ND's seamer Zak Gibson and batsman Daryl Mitchell, while Henry Shipley of Canterbury also gets a chance.
New Zealand ODI squad for the first two matches against South Africa in Hamilton on February 19 and Christchurch, February 22:
Kane Williamson (c),Trent Boult, Neil Broom, Lockie Ferguson, Colin de Grandhomme, Martin Guptill, Matt Henry, Tom Latham, James Neesham, Luke Ronchi, Mitchell Santner, Tim Southee, Ish Sodhi, Ross Taylor.
New Zealand squad for the only T20 international at Eden Park next Friday (February 17):
Williamson (c), Corey Anderson, Boult, Tom Bruce, Ferguson, de Grandhomme, Guptill, Colin Munro, Neesham, Ronchi, Santner, Sodhi, Southee, Ben Wheeler.
New Zealand XI to play South African in a warmup match at Eden Park on Tuesday (February 14):
Glenn Phillips, Broom, Henry Nicholls, Bruce, Taylor, Mark Chapman, Daryl Mitchell, Todd Astle, Adam Milne, Henry, Henry Shipley, Zak Gibson
More to come