Zealand on top after bowling out SA for 204 in 2nd ODI
However, any threat of an unlikely South Africa comeback was soon quelled with George Worker knocking a watchful 20 off 50, leaving Guptill to hit the winning runs and reach his century from the same ball.
The victory levels the three match series at 1-1, with the deciding match to be played in Durban on Wednesday.
Bracewell, playing in his first one-day global in more than two years, took a career-best 3 for 31 with his accurate medium-pacers.
The tourists never looked troubled in their reply as a 126 run opening stand between Guptill and Tom Latham (64) laid the platform for the emphatic win. The previous record of 114 had been set by Mark Greatbatch and Rod Latham – Tom’s father – in Auckland during the 1992 World Cup.
Tahir eventually ended the opening partnership getting Latham top edging a sweep to deep square leg.
The teams drew the Twenty20 series 1-1, with South Africa taking the first game and New Zealand coming back to win the second.
“We didn’t play the flawless game the other night but we only just got beaten chasing 300 so everyone’s still pretty upbeat”, he said. “The way the guys executed was fantastic – a great effort with the ball, then the way the openers batted”.
Credit must go to the way the New Zealand bowlers stifled the run rate though, with seamer Doug Bracewell the pick as he recorded figures of three for 31 in his 10 overs.
Bracewell took the next two wickets in a spell of 2 for 18 in six overs, with Rilee Rossouw (39) and David Miller (5) both falling to catches when they mistimed drives on a slow pitch.
The hosts were reeling at 134-6 in the 32.2 over before Farhaan Behardien and Vernon Philander (30 not out) shared a crucial 54-run partnership for the seventh wicket to give their side a fighting total. Imran Tahir was the next African to drop him in the 16th over while the batsman was 37, he was quick enough to pile up 24 runs in 12 overs since his first life.