Cummins has been labouring with a back problem and missed the eight-wicket wins over England in Perth and Brisbane which have given the hosts a 2-0 lead heading into the Adelaide Oval clash from December 17.
"We feel as though he'll be as best prepared as can be," Australia coach Andrew McDonald said of Cummins on Tuesday.
"We feel as though the simulation in the nets has got him skill ready. His body's ready to go. Barring anything else happening in the next week, I'd be expecting Pat to be tossing the coin and putting the blazer on."
Josh Hazlewood, who usually makes up the first-choice bowling attack with Cummins and Mitchell Starc, was absent from the squad after being ruled out of the remainder of the series because of Achilles and hamstring injuries.
"His rehabilitation timelines have been adjusted and he will now prepare for the ICC Men's T20 World Cup in India and Sri Lanka early next year," the team said.
Pace bowler Michael Neser retains his spot after being brought into the squad as an injury replacement and into the team in Brisbane at the expense of spinner Nathan Lyon.
The Queenslander, who took five for 42 in the second innings at the Gabba, may not get a chance to show his skills in Adelaide, however, with Cummins and Lyon expected to come into the side.
Neser and Brendan Doggett, who made his debut in the series opener in Perth, look set to make way for the celebrated duo as Australia look to lock up the series with two matches to spare.
Cummins was the only addition to the 15-man squad with opener Usman Khawaja retaining his spot despite having been left out of the team in Brisbane because of a back problem.
Australia squad for third Test in Adelaide:
Pat Cummins (captain), Scott Boland, Alex Carey (wk), Brendan Doggett, Cameron Green, Travis Head, Josh Inglis (wk), Usman Khawaja, Marnus Labuschagne, Nathan Lyon, Michael Neser, Steve Smith, Mitchell Starc, Jake Weatherald, Beau Webster