South Africa could claim top spot during tri-series
Australia's No.1 ranking on the line
Australia must remain undefeated for the remainder of the tri-series one-day tournament to ensure they hold onto top spot, after the Proteas closed the gap with their thumping seven-wicket win on Monday.
Even if Australia win the final on September 6, a loss against South Africa in their final round robin match next Tuesday doesn't look like it will be enough to keep the Proteas at bay.
The ICC rankings system is often difficult to put into context.
This is best evidenced by the fact South Africa have gone back to No.1 in Tests despite losing the mantle to the Australians when they suffered a crushing defeat in Cape Town in March.
Australia have been overtaken without playing another Test since that date.
However, to usurp their arch rivals in Tests and one-dayers would nonetheless ensure significant bragging rights for South Africa.
Star batsman Faf du Plessis admits rankings points will be foremost on his team's mind when they clash with Australia in another round robin fixture on Tuesday at Harare Sports Club.
"It's important for us, I must say," said du Plessis.
"A lot of teams say the rankings don't mean anything to them, but for us it's very important.
"To be the No.1 Test team in the world is a huge honour for us and took a lot of hard work to get there.
"A year or two ago in the one-day set up we were mid-table, so we've worked so hard to get to No.2 and it's important to play our best cricket and try and knock Australia off that No.1 spot to be No.1 in that format.
"It's something we're really striving to do."
Meanwhile, the South African and Australian camps have both talked down the importance of winning the toss in terms of winning the tri-series - despite records showing this is a bowl-first pitch.
South Africa's seven-wicket win over Australia on Wednesday illustrated how difficult it's to bowl second on a flat deck.
But Australian stand-in captain George Bailey says it's a good batting deck all round regardless of the time of day.
"The stats say that chasing on this ground is easier, but I don't think it plays a huge role," he said.
"If you bat first and make a huge total there's always big pressure on the guys chasing."