After AB de Villiers sent in New Zealand, Martin Guptill and Rob Nicol got off to their customary fast start in racing to 35 without loss from the opening four overs, but Guptill was soon left with some atoning to do after running out his partner for 23.
The wicket stunted New Zealand's momentum somewhat and that sedation could not be allowed to last long. Guptill and Brendon McCullum saw their side through to 79-1 at the halfway mark but, with Seddon Park's small boundaries likely to be a factor later in the evening, acceleration was needed.
The quest for quicker scoring was hindered in the 12th over when Guptill, three runs short of an eighth consecutive half-century, was caught in the deep to give Marchant de Lange his first international T20 wicket. McCullum soon followed which brought James Franklin to the crease.
The big left-hander proceeded to smack four sixes in five balls, sending the final one out of Seddon Park, giving the crowd at a sold out Seddon Park just a taste of what was to follow in the second innings.
SCOREBOARD
With two overs remaining, Franklin fell for a fine cameo of 28 from 10, with the Black Caps eventually finishing on 173-4, a target which always seemed attainable.
Attainable proved an understatement once Levi got underway. He took 17 from the second over and, once the Black Caps' spinners struck a double blow to reduce South Africa to 41-2, the fireworks began.
He brought up his 50 from just 25 balls in the seventh over and the milestone only spurred him on. Levi's eighth maximum brought up the South African 100 in the 10th over, and before long the records began to tumble.
His 11th six set a new mark in T20 internationals, and in the 14th over Levi brought up his century from just 45 balls, another record. At this point, the result of the match was perfunctory - the real intrigue surrounded what Levi's line in the scorecard would end up showing.
De Villiers, almost forgotten at the other end, hit the winning runs off the final ball of the 16th over, leaving Levi unbeaten on 117 - equalling Chris Gayle for the highest international T20 score. The two men finished with a 133-run partnership for the third wicket, to which de Villiers contributed just 39, giving South Africa the win and the momentum heading into the decider.