Brevis was the hero of South Africa's game-two win, cracking an unbeaten 125 off 56 balls to level the series at 1-1.
The 22-year-old was at it again on Saturday night, thumping 53 off 26 balls before being sent packing by a diving Glenn Maxwell catch in the deep.
Brevis signalled his intent early in his innings by pulling Ben Dwarshuis (0-37) onto the Cazalys Stadium roof.
But it was the 10th over - bowled by Hardie - when Brevis went into overdrive.
After a dot ball was followed by a two, Brevis proceeded to hit four consecutive sixes from the next four legal deliveries.
The first six - over cover - bounced onto the roof and out of the stadium.
Brevis sent his next six straight down the ground, with a crowd member crashing to the ground after running into a fence while trying to take a catch.
The next Hardie delivery was also sent straight down the ground - this time with no crowd injury - before the fourth was cut over cover.
A total of 27 runs was taken from the Hardie over, leaving South Africa well placed at 3-96 after 10 overs and 3-108 after 11.
But when Maxwell took a great diving catch off the bowling of Nathan Ellis to send Brevis packing in the 12th over, it proved to be a huge turning point.
South Africa were restricted to 62 runs from the final 8.2 overs as Australia's attack turned the screws.
"It was a big wicket, we knew that, so to see the back of him felt like a big moment," Ellis told Fox Sports.
"He's very hard to contain. I feel like he's come on in leaps and bounds. I feel like we are just seeing the start of him."
Ellis finished with 3-31 off four overs, while legspinner Adam Zampa was the most economical with 2-24 from his four overs.
Josh Hazlewood (2-30) set the tone early with the scalp of opener Aiden Markram (one) with the fifth ball of the innings, but Hardie finished with 0-33 from his two overs.
Brevis struck six sixes and one four, with Rassie van der Dussen (38no off 26) the only other notable scorer.
The Australian team wore black armbands to pay tribute to former Australia Test captain and coach Bob Simpson, who died at the age of 89.
A minute's silence was held before the game began.