A humdinger at Hamilton saw South Africa edge New Zealand by four wickets in a rain-curtailed affair. Opting to field first, South Africa, aided by Chris Morris, wrecked New Zealand's top order even as skipper Williamson made a fighting half-century.
The innings found impetus towards the end as Southee and de Grandhomme plundered the bowling in a 51-run stand. 207 in 34 overs is child's play these days and Quinton de Kock seemed to make light work of the chase with a superb half-century.
However, some reckless batting thereafter meant South Africa were in a spot of bother but AB de Villiers and Andile Phehlukwayo combined in a superb 54-run stand that shifted the game in South Africa's favour.
Here are the talking points from the first ODI in Hamilton.
#5 Brownlie-Latham set for showdown
New Zealand have a big problem to deal with before the Champions Trophy – their opening combination. While Martin Guptill is expected to be fit and firing by the third ODI, the other spot is a toss up between Tom Latham and Dean Brownlie.
All was going well for Latham until he hit a rough patch in ODIs. The runs dried up and his overall average took a beating. The manner in which he crumbled against top quality seamers like Starc and Hazlewood prompted the selectors to rush Brownlie back into the squad after a long hiatus.
The bearded Brownlie smashed a useful half-century in his comeback match, and today, in the first ODI of the series against the Proteas, he looked good before being dismissed for 31. Meanwhile, Latham departed for a duck off 11 balls.
#4 Chris Morris rocking his new role as opening bowler
Chris Morris has thrived on responsibility and once again proved that he is the right man to open the bowling attack with Kagiso Rabada in ODIs. The pacer had bowled with pace and venom against Lanka towards the end of that series as well.
Morris proceeded to bowl a superb opening spell in the only T20 in New Zealand returning figures of 3-1-10-2. The all-rounder was at his best once again today dismissing Tom Latham for a duck early on.
He had Dean Brownlie, Ross Taylor and Neil Broom in a superb burst of seam bowling. The only batsman to resist was Williamson but even he struggled to find the middle of the bat against a fiery Morris. The all-rounder has what it takes to be the new-ball bowler for the Proteas, however, he does need to improve his bowling at the death.
#3 Kane Williamson threatens to fire
The New Zealand skipper Kane Williamson has been lauded as one of the five best batsmen in world cricket today. A perfectionist, Williamson has one of the best technique among modern batsman.
Walking in at 3, the skipper had to contend with a fired up Chris Morris and a charging Rabada. He made his intentions clear pretty early against Imran Tahir, dismissing him over the mid-wicket fence.
While Morris continued to wreak havoc at the other end, Williamson stood like a rock, holding together the New Zealand batting line-up. He took on the wrist spinners, Tahir and Shamsi, but eventually fell to the latter after inside-edging onto his stumps.
#2 Southee plunders and then gets plundered
Tim Southee is a handy lower order batsman and this has been proven ever since his debut match for the Black Caps. The experienced seamer proved to be a thorn in South Africa’s side in the death overs as he made a quick fire 24 off 13 balls.
The fast bowler slammed Chris Morris for three fours and a six off the final over to help the Kiwis cross the 200 mark in a rain-shortened affair. He combined with de Grandhomme in a 51-run stand for the eighth wicket.
However, he returned the favour when the Kiwis bowled as Phehlukwayo and de Villiers plundered 12 off his final over to win the game for South Africa. Southee returned unimpressive figures of 2/47, despite getting Duminy and Behardien off successive balls.
#1 Phehlukwayo playing the part to perfection
Big things weren't expected of Andile Phehlukwayo when he was handed his ODI debut. He was expected to be another bits and pieces all-rounder in South Africa's ODI jigsaw puzzle.
But the all-rounder surprised everyone by returning as the top wicket taker in the Australian series. He even played a superb cameo with the bat along with David Miller in a 371 run-chase.
As if to prove that knock was no fluke, Phehlukwayo combined with skipper, de Villiers set up a game-changing partnership. He made 29 of the 54 runs in the partnership, including two sixes in the last two overs that virtually sealed the game for the visitors.