The match will take place at the Gabba in Brisbane on January 9, four days before the start of the traditional triangular One-day series featuring Australia, the Proteas and Sri Lanka.
The increase in Australian Twenty20 matches stems from sell-out crowds at matches between Western Australia and Victoria in Perth and Australia 'A' and Pakistan in Adelaide last January.
Australia has already played a Twenty20 match in downing New Zealand in Auckland last February and will play England in a shortened match on June 13, at the start of the Ashes tour.
Australian coach John Buchanan and One-day star Andrew Symonds have also voiced their support for proposed changes to the 50-over version.
The International Cricket Council (ICC) is considering allowing teams to make football-style substitutions in One-day Internationals, which would lead to batsmen being replaced mid-innings without being dismissed.
Increasing fielding restrictions from 15 to 20 overs, and allowing captains to dictate when they are applied are also among the proposals.
Symonds said the proposed innovations could help freshen up 50-over matches.
"I do hear a lot of people talk about the middle part of One-day Internationals being quite boring now, like everyone's just knocking it around and players aren't trying to hit as many boundaries," Symonds told a press conference in Melbourne on Friday.
"But now if they can inject this 10-over period for more four and six-hitting, that will take the boring aspect and the aspect of predictability out of it, where a captain can actually call on a certain player to go out and try and achieve something for his team."
Buchanan said he believed Australia could improve its 50-over capabilities provided it adapted well to the tactics.
"We have a very good depth and an all-round side, so I think that at the moment it looks like it will give us some advantage," he said at the press conference.