|Third Vitality Twenty20 International, Ageas Bowl|
|South Africa 191-5 (20 overs) Hendricks 70 (50), Markram 51* (36); Willey 3-25|
|England 101 (16.4 overs) Bairstow 27 (30); Shamsi 5-24|
|South Africa won by 90 runs; win series 2-1|
A dismal batting display saw a pitiful England suffer a heavy 90-run defeat in the deciding Twenty20 against South Africa to lose the series 2-1.
Chasing 192 to win at the Ageas Bowl, England were blunt with the bat, going 55 balls without hitting a boundary at one stage, before being dismissed for 101 in 16.4 overs.
It is the fourth time in six T20s this summer that England have been bowled out and there was another failure for Jason Roy, who made 17 off 18 balls.
Jonny Bairstow top-scored with 27, while South Africa's left-arm wrist spinner Tabraiz Shamsi ripped through England with career-best figures of 5-24.
Defeat means England have lost a third successive T20 series, after defeats by West Indies and India this year, for the first time and they have failed to win a white-ball series in a home summer for the first time since 2013.
Reeza Hendricks had earlier made 70 off 50 balls and Aiden Markram hit an unbeaten 51 off 36 as the Proteas brilliantly paced their innings to post 191-5.
The returning David Willey was the pick of England's bowlers, taking 3-25, including removing Quinton de Kock in a wicket maiden at the start of the innings.
England are next in action when a three-Test series against South Africa starts at Lord's on 17 August.
Their next T20 assignment will come in a seven-game tour of Pakistan in late September before three T20s against Australia leading into this year's T20 World Cup in October and November.
England's top-order struggles continue
Much of England's white-ball success over the last six years has been built on their top-order power. This summer it simply has not produced.
Roy has contributed just 76 runs in six games, at a strike-rate of 77.55, compared to a career figure of 137.77, with the 32-year-old unable to play with any fluency.
His dismissal was one of frustration as he looked to pull fast bowler Anrich Nortje but could only feather through to Proteas keeper De Kock.
Jos Buttler got another start but sliced Keshav Maharaj to short third, with England only able to hit two boundaries in the powerplay, in comparison to South Africa's 10.
The innings never had any rhythm, with eight England batters caught in a fine South Africa fielding performance - the highlight being Tristan Stubbs' stunning one-handed, diving grab to remove Moeen Ali.
There were ironic cheers round the Ageas Bowl when Bairstow flicked away for four to end the boundary drought, but Sam Curran and Willey then fell in successive balls.
Bairstow, who was looking to farm the strike and pull off a ridiculous victory, holed out to deep mid-wicket to wrap up a timid display.
England have been unable to put together two batting performances in a row this summer and with a World Cup just 10 competitive games away that will be of grave concern to captain Buttler and head coach Matthew Mott.
Patient approach reaps rewards for Proteas
After De Kock was bowled by Willey, Rilee Rossouw attacked before he too was bowled by a beautiful, turning delivery from Moeen.
It left Hendricks to anchor the innings and, after a fortuitous start with several edges past his stumps, he did so superbly, bring up his third consecutive fifty of the series.
The tourists were patient, going 40 balls without a boundary at one point but hitting the gaps well on a big Ageas Bowl surface, before Hendricks kicked on and fell, top-edging Chris Jordan to Buttler.
Markram then combined brilliantly with David Miller, who made an excellent nine-ball 22, as they hit four successive fours in their 41-run stand from 17 balls to post a total that proved well beyond England.
England are still experimenting in search of the first choice XI for the World Cup in Australia this autumn and here they used bowlers in different roles to usual.
Sam Curran was deployed more in the middle overs and was fairly defensive, while Jordan had a difficult day in going for 52 from his four overs.
It left Willey, who has had a mixed record at the end of the innings, to bowl the final over and he dismissed Miller and Stubbs to cap off an impressive day.
However, it was another bowling performance that left questions about how England will cope in a major event if the likes of injured pace bowlers Jofra Archer, Mark Wood, Chris Woakes and Saqib Mahmood are all unavailable.
'We lacked intent and confidence' - reaction
England captain Jos Buttler: "It was a really good score on the board but I still had confidence in the group. We like to try and challenge ourselves with the bat but the way we played, the way we went down, is the most disappointing thing.
"We lacked intent and confidence and didn't manage to put the opposition under pressure. We never able to wrestle the initiative."
South Africa captain David Miller: "It is a privilege to play 100 caps for your country and to top it off with a performance like today from the boys was just phenomenal.
"We have come on leaps and bounds in the last 18 months and we've learned a lot. The character the guys are showing and the way they are putting their hands up in key moments is what we want."
Player of the match Tabraiz Shamsi: "I really enjoyed myself but huge credit to the batsmen. They put on an above par score and also the guys who bowled before me.
"Before I came to the game, my wife casually said she wanted four wickets. That's why I was a bit more animated with celebrations today."