Smith, Warner stand down, Paine named acting captain

Tim Paine has taken over Australian captaincy duties for the rest of the third Test against South Africa after Steve Smith and vice-captain David Warner opted to stand down over the tampering scandal.

The news was announced by Cricket Australia chief executive James Sutherland just minutes before Australia were booed onto the Cape Town field as play resumed on day four.

Smith, who travelled to the ground on the team bus and then sequestered himself from the team, will continue as a regular member of the team alongside Warner.

The skipper's 10 ashen-faced teammates all went through their standard pre-play routines on the morning of day four but he was nowhere to be seen.

"This Test match needs to proceed, and in the interim we will continue to investigate this matter with the urgency that it demands," Sutherland said.

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Steve Smith and Tim Paine. Pic: Getty

Unconfirmed reports out of India say Smith has already been dumped as captain of the Indian Premier League's Rajasthan Royals.

The IPL is due to begin on April 7, just days after the fourth Test between Australia and South Africa is scheduled to finish.

Cameron Bancroft has been charged by the ICC over his acts on Saturday, but Smith -- despite admitting a role in the tampering -- is yet to be cited.

The wicketkeeper Paine, 33, almost quit cricket less than 12 months ago as he struggled to retain his place in Tasmania's Sheffield Shield side.

He was set to begin working for Kookaburra until he made a stunning return to Test cricket ahead of the Ashes.

Paine appears to have jumped the queue to become acting captain, with Nathan Lyon, Josh Hazlewood and Mitchell Starc previously named as members of a leadership group.

Smith had said on Saturday that the plan to change the condition of the ball was hatched in a discussion with the leadership group, though he did not clarify who those players were.

He insisted coaching staff, including Darren Lehmann, were not aware of the premeditated plan and that his side have never tried using tape to scuff the ball before.

Smith, with the exception of a couple of incidents on a spiteful tour of India last year, had enjoyed a squeaky-clean start to his century-laden captaincy.

The ugly episode has prompted an outpouring of shock and condemnation, with the Australian Sports Commission leading calls for Smith and "any other members of the team leadership group or coaching staff who had prior awareness" to be stood down.

"I've spoken with David Peever, the chairman of Cricket Australia, a few moments ago and I've expressed to him very clearly and unequivocally my disappointment and my concern," Prime Minister Malcolm Turnbull said.

with AAP