Tillakaratne Dilshan's superb unbeaten 74 guided Sri Lanka to a six-wicket victory over South Africa that ensured they retained their place at the top of the world Twenty20 rankings.
The Proteas had already clinched the series having won the first two fixtures in the three-match rubber, responding strongly following their 4-1 drubbing in the recent one-day international series.
Their bid for a clean sweep looked on course as they posted a solid total of 163-3 from their 20 overs, with half-centuries from skipper Faf du Plessis (85) and JP Duminy (51).
But once Dilshan and opening partner Mahela Jayawardene (33) had got the hosts off to a blistering start in their reply they always looked likely winners and duly got over the line with 11 balls to spare to remain above Pakistan in the standings for the game's shortest format.
The tourists won the toss and elected to bat, but made a less than ideal start when Henry Davids fell lbw to Nuwan Kulasekara from the first ball of the innings.
Quinton de Kock and Du Plessis steadily rebuilt before the former was adjudged leg before to Ajantha Mendis with the score on 45.
That brought Duminy to the crease, and he and his captain played aggressively, taking the game to the Sri Lanka attack.
Their entertaining 112-run partnership eventually came to an end in the final over when Du Plessis, who racked up 10 fours and three maximums during his career-best innings in this format, was bowled by Suranga Lakmal.
The total appeared competitive, but South Africa were quickly on the back foot as the Sri Lankan openers blazed out of the blocks.
The score was 67 without loss inside six overs until Wayne Parnell tempted Jayawardene into one shot too many, with his attempted drive finding AB de Villiers at extra cover.
Kusal Perera went for just one as Sri Lanka briefly wobbled, but Dilshan - who struck nine fours and two sixes in his 51-ball innings - continued fluently with help from Dinesh Chandimal (14) and Angelo Mathews (14) before Thisara Perera's 11-ball 25 saw the hosts to victory.