Australia have gone from embarrassments to tri-series finalists within 48 hours after crushing South Africa in Harare.

The fighting character Darren Lehmann’s side has consistently shown since last summer came to the fore as Australia saved face from their loss to Zimbabwe the only way they could – booking a rematch against fierce rivals the Proteas in Saturday’s one-day decider.

Defeat on Tuesday could have left them on the brink of shock elimination, but led by the explosive brilliance of allrounder Mitchell Marsh, Australia powered to a 62-run bonus point victory after setting South Africa a target of 288 to win.

Even with Faf du Plessis’ second hundred from as many matches against Australia, the Proteas were no match.

Selectors were questioned by captain Michael Clarke and critics alike following the calamitous performance against Zimbabwe.

But against South Africa every change made by those picking the team proved a masterstroke – starting with the decision to push big-hitting Mitchell Marsh back to No.6.

There the 22-year-old belted a match-winning 86 not out from 51 balls which included seven sixes.

Not only did Marsh’s match-winning 86 off 51 illustrate his incredible power, it showed that at 22, he’s capable of performing under significant pressure.

Stalling at 5-187 after 42 overs, Australia looked set to follow up their sub-standard batting display against Zimbabwe with another mediocre total.

But then Marsh at No.6 changed the course of the game in the 47th.

And not against just any bowler, but Steyn – one of the most successful wicket-takers of the modern era.

For the first time in his career, Steyn was clubbed for three consecutive sixes, two which disappeared back down the ground and resulted in balls being replaced.

Marsh smashed 64 from the last 24 balls he faced as Australia added 70 in the final five overs to rise to 7-287.

His seven sixes were the most in an Australian innings since Shane Watson hammered 15 in a giant ton against Bangladesh in 2011.

“When it (selection) works it makes it look very easy,” said stand-in captain George Bailey.

Marsh, who also took 2-23 with the ball, declared Australia had dug deep to put themselves back in business.

“Obviously it showed a bit of character,” he said.

“There’s always pressure when you play big games against good teams but we were really excited about the opportunity to bounce back from the other day.

“It was very disappointing, but this goes to show that when we come with the right attitude we can win any game of cricket.”

Australia recalled Mitchell Johnson, Steve Smith and Kane Richardson to the line-up, and all three made their mark.

Particularly spearhead Johnson (2-30), who blasted two of David Miller’s stumps clean out of the ground to send a message that he’s a force to be reckoned with even on a slow track.

The faith of selectors in Phil Hughes at the top of the order was also justified as he stroked a brilliant 85 – his second half century of the tour.

“Mitch (Johnson) is obviously a nice inclusion. Kane Richardson has been really good for us and Smith (36) can fit anywhere in a one-day side. I thought he looked the part at No.3,” said Bailey.

On Sunday against the No.10 team in the world, Australia were a rabble in every department.

The inevitable fallout included a public differing of opinion between Clarke and Lehmann on how team selection meetings should be handled in the media.

But against South Africa, Australia put the drama to one side and produced some special moments.

Brad Haddin’s spectacular grab down the leg-side off Marsh to remove danger man Hashim Amla was extraordinary.

Earlier, Marsh dazzled with the bat as Australia clubbed 70 runs from the final five overs to lift them out of the trouble they were in at 5-187.

Captain George Bailey admitted the horrifying thought that they could be sent packing early from the tournament, with Zimbabwe sneaking into the final, had crossed their minds.

“Oh yeah, that was a possibility,” said Bailey.

“We want to set the standards we want and nail them.”