It was a good day for Australian cricket in more ways than one.

Aaron Finch blasted a mighty century, and Steve Smith a masterful 73 not out, to lay the groundwork for Australia’s 73-run victory over South Africa at Manuka Oval in Canberra.

The result gave Australia a 2-1 lead in the best-of-five series which, in truth, will be long forgotten before this endless, mixed-up summer is done and dusted.

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Elsewhere, though, there were indications that things might be falling into place on a more meaningful front.

Peter Siddle, who has been under pressure to hold his place in the Test side in the lead-up to the series against India, hit his straps at the Adelaide Oval, taking 5-31 to bowl Victoria to victory over South Australia and virtually cement his spot.

And Ryan Harris, who is once again on the comeback trail from injury, had a superb match in Queensland’s win over New South Wales at the Gabba, the venue for the first Test, starting on December 4.

Harris had match figures of 7-118 and thrashed a run a ball half-century for the Bulls, almost ensuring that the three-piece band of Harris, Siddle and Mitchell Johnson would be back together for the first Test.

At Manuka Oval, meanwhile, Finch and Hashim Amla hit contrasting centuries in a high scoring affair.

While Finch was ferocious, Amla looked every part a zen master in response, peeling off the runs with textbook strokes and exquisite timing.

The veteran passed 100 while sharing a 76-run stand with AB de Villiers, as two of the best batsmen in the world looked set and the visitors had seven wickets in hand.

The equation was a reasonably straightforward 106 runs needed from 77 balls when things started to go pear-shaped for the Proteas.

De Villiers, who brought up his half-century off 32 deliveries, went shortly after being dropped by Mitchell Marsh.

He was trapped lbw by Kane Richardson, one of three inclusions as Australia rejigged their attack and rested Johnson.

De Villiers reviewed the decision, but third umpire Billy Bowden was unable to help him.

The next over, Amla was clean bowled by Josh Hazlewood for 102 – his greatest ODI score against Australia.

Mitchell Starc kept the foot on the throat, dismissing David Miller, Vernon Philander and Dale Steyn in quick succession as the hosts steamed towards victory.

South Africa finished on 9-256, with Imran Tahir unable to bat.

The contrast between the bouncy WACA pitch and the batsman-friendly deck in Canberra could not have been more stark.

Morne Morkel, man of the match in Perth on Sunday when he claimed 5-21, went from behemoth beanpole to powerless praying mantis.

Morkel finished with 2-84 from 10 overs – his worst ODI figures.

Philander (1-70) also copped some brutal treatment, while it was the first time since 2009 that Steyn went wicketless against Australia in a one-dayer.

Finch smashed his fifth ODI century, while Smith’s stocks climbed further.

Finch and David Warner (53) made a typically aggressive start to the game, racing to 0-118 before Philander snagged a breakthrough to end the 20th over.

Finch continued to plunder runs alongside Shane Watson (40) and Smith before he was clean bowled by part-timer de Villiers in the 41st over.

It was one of few sources of joy for the Proteas’ skipper, who watched the hosts take 19 runs off the final over in front of a crowd of 10,583.

With AAP