Australia head into Thursday's World Cup semi-final against South Africa with the same excitement in the dressing room that propelled them to their maiden triumph in the T20 World Cup in 2021, Glenn Maxwell said.

Maxwell was part of Aaron Finch's groundbreaking squad in the United Arab Emirates in 2021 and scored an unbeaten 28 in the final against New Zealand.

Coming off an incredible match-winning double-century against Afghanistan last week, the mercurial all-rounder said his team had a huge boost from the victory over the South Asian side and were well-placed to carry on and claim a record-extending sixth ODI World Cup title.

"The excitement of that match has given us a whole new belief going forward," Maxwell said in an interview with Australian broadcaster Fox Sports.

"It reminded me of the T20 World Cup in 2021. The same sort of feeling.

"The feeling around the group was energetic, electric, exciting and everyone felt they were heading towards the same end goal.

"And who knows, it could be the same thing here."

Having battled a full body cramp when batting against Afghanistan, Maxwell guided Australia to victory with an unbeaten 201 off 128 balls, relying mostly on his hands and reflexes to smash the bowlers around the ground.

The knock was quickly branded the greatest ODI innings of all-time by a slew of former players and pundits.

With five runs left to win and to bring up Australia's first double-century in ODIs, Maxwell said he was absolutely certain that he would score a six off spinner Mujeeb Ur Rahman to achieve both targets.

He duly clobbered Mujeeb over the deep midwicket fence, his third six of the over.

"It may sound arrogant and over-confident but (it was) because I knew I had the short boundary, because I knew Mujeeb," he said.

"We've played against and with each other. I've spent a whole IPL training with him, having little contests and spending a lot of time with him.

"And I'd faced most of his overs he'd bowled at that stage. I just felt like, 'I've got this ... I know I don't have to hit it out of the middle to get a six'."