Once Amla settled in, the result was never in doubt, his classy 92 off 107 balls guiding South Africa home with a whopping 70 balls to spare.
His strike rate is superior to all South Africa's leading batsmen, past and present, bar de Villiers and his average is a cracking 56.1.
His strokeplay was superb. At one point he took five boundaries from seamers Kyle Mills and Tim Southee in the space of 10 deliveries. His driving was exquisite, his placement top class.
New Zealand needed all the breaks to go their way, and getting Jacques Kallis in the third over was a decent start. However back-to-back stands between Amla and Faf du Plessis, then Amla and J-P. Duminy banged nails into the New Zealand cause and by the time Amla departed to a beauty from legspinner Tarun Nethula the job was all but done.
Acting captain Brendon McCullum had talked of the importance of New Zealand winning the critical moments if they were to peg back South Africa.
A shame, then, that it was McCullum's dismissal, 15 shy of a fifth ODI hundred, which put the skids under the New Zealand innings.
He and Martin Guptill had set the innings nicely with their 107-run second wicket stand.
Starting from the dismissal of Kane Williamson, New Zealand lost five for 23 from 33 balls. It ripped the heart out of the New Zealand innings. Put another way, New Zealand's last nine wickets fell for only 99 in 22.3 overs.
This pitch is the batsman's banker in New Zealand, which made the sorry slide all the more depressing.
McCullum, in his 200th ODI, the sixth New Zealander to the mark, needed to press on.
It hadn't been a vintage innings, a couple of ugly swings and misses and Lonwabo Tsotsobe dropped a return catch on 18. But they were balanced by some crunching cuts and drives and twice he cleared the rope.
His downfall came attempting to find the stands a third time, flicking Tsotsobe to deep square leg. His frustration was evident, and understandable. It came at a time when, quite apart from having a big century for the taking, he was needed to anchor the innings through to the end.
Instead Jesse Ryder, feet not moving, James Franklin, edging a lifter down on to his stumps, and Kyle Mills, fending to gully, were gone in a jiffy and it was all uphill.