Archer, in just his second match for England after his two-year injury nightmare, bowled with pace and intelligence to take 6 for 40 as South Africa were unable to chase down 347 for victory.
Jos Buttler suggested his player of the match award should have been in the grasp of Jofra Archer after the England seamer recorded his best white-ball international figures to propel his side to a first win in seven ODIs.
Archer, in just his second match for England after a two-year injury nightmare, bowled with pace and intelligence to take 6 for 40 in Kimberley as South Africa were unable to chase down 347 for victory.
His haul included the key scalps of Rassie van der Dussen, Aiden Markram and David Miller in the first half of the innings, and then a well set Heinrich Klaasen late on as the Proteas built a platform from which they were aiming to complete a series whitewash.
It was an encouraging outing for Archer in a year which will see England defend their World Cup title in India, and Buttler - who earlier made 131 - said that perhaps, all things considered, his teammate deserved more credit and a commemorative trophy to go with his matchball.
Jos Buttler made 131 for England against South Africa [Getty Images]
"Jofra Archer's performance tonight was fantastic and probably deserving of the player of the match award," he said.
"When the game is in the balance, to come back and take the wicket of Heinrich Klaasen broke the game open again for us."
As well as Buttler, Dawid Malan reached three figures for England, with the pair sharing a fourth-wicket stand worth 232 - the joint fifth best in men's ODI history.
The partnership rescued the tourists from 14 for 3, and a delighted Buttler said afterwards that triple-figure individual scores are one of the parts of this trip which has pleased him the most.
"Both teams wanted to bowl first. South Africa struck with early wickets and it wasn't straightforward at the top. To build that partnership with Dawid Malan and for us to go on and post 340 from 20 or 25 for 3 from 10 overs is a fantastic effort," he said.
Buttler felt Jofra Archer should have been given the player of the match award [Getty Images]
"We spoke about trying to build a partnership, we felt like it would get easier at some point, and it's not the biggest ground so we felt like we would be able to catch up at the end. We've got some excellent hitters to follow us so we wanted to extend the partnership as long as possible.
"Guys going on to get hundreds is something we've spoken about, in the English summer we didn't do as well as we would have liked."
With series crowbarred into the schedule to please broadcasters and satisfy pandemic commitments, England's limited-overs calendar is a bit of a mess at present.
These three matches in South Africa have been squeezed in during two major franchise T20 tournaments, to which several England players are now returning, while a Test tour of New Zealand is imminent. Then follows a white-ball trip to Bangladesh, which several players are expected to miss in favour of the Pakistan Super League: Alex Hales, Sam Billings and James Vince among them.
It is not ideal in a World Cup year - as both Ben Stokes and Moeen Ali have implied with recent public comments. And, in his softly-spoken way, Buttler added his frustration on Wednesday.
Archer claimed 6 for 40 with the ball [Getty Images]
"Bar recent results we've got a good thing going and we're building nicely," he said.
"The schedule is just something we have to try to work with as much as possible.
"It's been great to be here as a group for just a short period of time - a little bit more than a week - but we'll look forward to joining up again in Bangladesh in a few weeks' time.
"It's nice for us to finish with a win today. Bar 10 or 15 overs of the chase in the first ODI, we've played some brilliant cricket. It's been a hard-fought series. Today, we're delighted to get a win."
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