Australia 129 for 4 (Finch 39, Tahir 2-21) beat South Africa 128 for 7 (De Kock 41, Starc 2-16) by six wickets
Scorecard and ball-by-ball details
Australia ended their South African tour as they started it: with an emphatic win in Centurion. They overwhelmed the hosts in the longest and shortest format at the venue to claim both trophies on offer in their month-long visit and winning the T20 series by a 2-0 margin.
In conditions that offered swing and seam movement, Australia's bowlers restricted South Africa to a below-par total. Their batsmen, sans David Warner who was rested for the final game, chased it down like a team in a hurry and they are - to get to the World T20 in Bangladesh.
Australia will go there far more prepared than South Africa after a clinical performance that exposed South Africa's vulnerabilities, especially without their two pace spearheads. Neither Dale Steyn nor Morne Morkel were included in the XI as they complete their rehabilitation from hamstring and shoulder injuries respectively but even they may have found it difficult to defend this total.
South Africa fell significantly below the average first innings score at this ground of 197. That number does not take into account the sluggish nature of the surface given the unseasonal wet weather but Australia showed run scoring was not as difficult as South Africa made it look.
They were pinned down by Australia's speedy assessment of the conditions and tactical nous in exploiting it. Mitchell Starc found extra bounce immediately and hit Quinton de Kock at the end of his first over - a maiden, which set the tone for Australia's effort in the field.
Although de Kock persisted and succeeded to some extent in moving forward to Nathan Coulter-Nile, Australia drew first blood when Starc trapped Hashim Amla lbw with a full delivery that swung into him and caught him in the crease.
George Bailey introduced spin in the fourth over and Glenn Maxwell had reward almost immediately. Faf du Plessis looked to clear mid-off but Brad Hogg proved age is nothing but a number. He backpedalled and took the catch to put South Africa in trouble at 20 for 2.
That was where South Africa made a tactical error. Instead of sending in their best batsman, AB de Villiers, JP Duminy was deployed at No.4. He smoked two gorgeous boundaries before becoming the second man to give it away. Duminy picked out the man at deep cover which meant de Villiers faced pressure from the moment he walked out.
He also found a fielder, at deep square leg, which brought South Africa's finishers to the crease too early. David Miller tried to drive on the up and was caught at short cover. De Kock, who saw very little of the strike after the first six overs, was a victim of turn and Albie Morkel was yorked after striking two meaty sixes.
South Africa managed 24 runs off the last three overs. Their highest partnership was only 25 and it was always unlikely to be enough.
Even though the juggling of their batting line-up did not work, South Africa chose to do the same with their bowling. They opened with Duminy but the gamble did not pay off.
Aaron Finch took advantage of anything short or wide and after Duminy, South Africa's slew of left-arm seamers offered plenty. By the end of the fourth over, Finch had brought Australia's required run-rate down to less than a run a ball.
Finch and Cameron White posted the highest partnership in the game, 43, and the contest was all but decided there. It still required Shane Watson to anchor the rest of the chase after Finch mis-timed his slog sweep off Imran Tahir.
The legspinner was the only positive for South Africa in the field. He bowled smartly, mixing his googly with his stock delivery and tossing it up generously in search of a wicket. He even claimed a second one, that of Watson, who also got the slog sweep wrong but by then, the deal was sealed.
Watson had already taken 12 off three balls off Morkel's over and Maxwell added to the returnee's misery. Morkel's second over cost 18 runs and by then Australia only needed 26 runs off the last eight overs. They got there in three to emphasise their dominance over South Africa and leave du Plessis and Russell Domingo with questions to be answered about how they will make best use of their resources at the World T20.