Steve Smith has approximately 24 hours to show why he deserves to stay on as skipper, with Cricket Australia (CA) chief executive James Sutherland en route to South Africa as his organisation starts to urgently probe the ball-tampering scandal.
CA's integrity chief Iain Roy and team performance manager Pat Howard have landed in Cape Town and started their formal review of Smith's cheating confession that rocked world cricket.
Sutherland, who is under immense pressure to strip Smith of the captaincy, will travel to Johannesburg and meet with Roy and Howard on Tuesday before discussing likely punishments with CA's board.
Warner's vice-captaincy also hangs in the balance, with the opener shaping as another enforced omission for the fourth Test.
Smith has already been slapped with a one-Test ban by the International Cricket Council and will miss the series finale that starts in Johannesburg on Friday.
The fate of Smith, Warner and Cameron Bancroft is expected to be become clear in the early hours of Wednesday morning (NZT).
The ICC didn't ban Bancroft, instead punishing his ball-tampering charge with a hefty fine and three demerit points, but CA may not be so forgiving.
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Bancroft carried out the plan on Saturday then attempted to hide the evidence from umpires, while Warner was also involved in the initial discussion.
Any player or member of support staff who conspired to use sticky tape in an illegal effort to scuff the ball at Newlands are also likely to be sanctioned.
CA has the power to mete out lifetime bans from the sport but the governing body is unlikely to opt for such an extreme response.
Australian Cricketers' Association (ACA) chief Alistair Nicholson is on deck in Cape Town, where a series of crisis talks are unfolding.
Not since the "homeworkgate" saga of 2013, when Shane Watson was banned, flew home, copped criticism from Howard then returned to India and became Australia's 44th Test captain, has there been such instability in Australian cricket.
On that occasion, four players were given one-Test suspensions for not completing written feedback to then coach Mickey Arthur.
Now, Smith has admitted he rubber-stamped ball tampering. The fresh-faced leader's moral compass was corrupted by a desperation to win.
Tim Paine, who is set to lead Australia in the fourth Test, says Smith and Bancroft are "struggling" as the full extent of the backlash becomes clear.
"They're not great. It's been a horrible 24 hours, they're struggling but probably the reality and the enormity of what's happened is starting to sink in," Paine said after his team's 322-run loss at Newlands.
"I don't think we all would have expected this to be as big as it has been and particularly the fallout that we have seen from back home."
Paine is expected to formally become Australia's 46th Test captain, having filled in when Smith and Warner stood down from their leadership roles for the rest of the third Test on Sunday.
The Tasmanian wouldn't be drawn on whether Smith and coach Darren Lehmann should continue in their posts.
Paine also wouldn't entertain the prospect of replacing Smith in a full-time capacity.
"There'll be a review this week. I'm not sure what's going to happen," he said.
"I don't think anyone is."