South Africa clinched a 2-1 Twenty20 International series win over England in dominant fashion with a 90-run victory at the Ageas Bowl.

Despite losing Quinton de Kock for a duck in the first over of the decider in Southampton on Sunday, the Proteas posted an imposing 191-5 as Reeza Hendricks and Aiden Markram thrived with the bat.

After a 55-run stand with Rilee Rossouw, who fired 31 off 18 balls, Hendricks (70) and Markram (51 not out) combined for a key 87-run third-wicket partnership.

Markram had support late in the innings from captain David Miller - who hit 22 off just nine balls - and the pair at one point combining for five fours in the space of six deliveries.

Miller struck South Africa's sole six and Tristan Stubbs hit two fours in the final over to push South Africa beyond 190, which England never threatened to reach after Jos Buttler (14) and Jason Roy (17) had both departed during the powerplay.

Tabraiz Shamsi (5-24) was the star of the show as the spinner ensured the wickets continue to tumble around Jonny Bairstow, who was the last man to fall on 27 when he slog-swept Keshav Maharaj to deep midwicket.

Buttler still waiting for series win

England's new white-ball skipper Buttler remains without a win from his first four series since taking the job, this defeat following a drawn ODI series with South Africa and 2-1 losses to India in both limited-overs formats. The manner of Sunday's defeat suggests he and his side have a long way to go if they are to contend at the T20 World Cup this year.

Shamsi puts England in a spin

Shamsi's five-for was the first of his T20I career. Both of his previous four-wicket hauls in the format came last year against Ireland and Pakistan. The Proteas have now won four of their past five T20I series, continuing their fine form in England after a 2-2 draw with India earlier in the year.