Smith's future as a player and, particularly, as captain is in doubt after he admitted to hatching a plan to tamper the ball during the third Test against South Africa.

The Australian team was embroiled in a furore not seen since India threatened to go home mid-tour in 2007-08 and even the infamous under-arm incident against New Zealand of 1981 after it was caught attempting to alter the condition of the ball on the third day of play against the Proteas.

Cameron Bancroft used a yellow piece of tape to illegally tamper with the ball, a plan that was devised by the team's leadership group during the lunch break. This group is likely to have featured Smith, vice-captain David Warner and fast bowlers Mitchell Starc and Josh Hazlewood but, according to Smith, not Lehmann.

CA chief executive James Sutherland said on Sunday integrity chief Iain Roy and team-performance boss Pat Howard had flown to South Africa and would begin a comprehensive review.

Smith remains the centre-piece of the investigation, with Sutherland not guaranteeing he would remain in the role come the fourth Test against the Proteas in Johannesburg.

"Steve Smith is currently the captain of the Australian team. We are working through a process ... once we have got a clearer picture of the facts and once we understand things and once Iain submits his report, then we will be able to make further comment," he said.

Sutherland was peppered with questions about Smith, particularly as the skipper had admitted to cheating. But he said he not spoken with Smith nor did he know who had been part of the leadership group which made the ill-fated decision.

"In recent times, as most of you know, I have had reason to speak to Steve about the team's behaviour ... as I said, I have very strong and clear views about the responsibility of the Australian cricket team to play the game in the right spirit and I don't anyone will be under any illusions there in the team as to what I think about this," Sutherland said.

He said the ongoing Test needed to conclude and "in the course of the next couple of days we will get to bottom of this and we will take appropriate action".

"We are shocked and disappointed at what we saw on the field," he said.

A decision on Smith is expected within days once the "process" concludes while Sutherland also did not endorse Lehmann when asked if the South Australian should consider his own future.

"The way you framed that question, that's a question for Darren Lehmann but, from a Cricket Australia perspective, our responsibility right now is to understand the facts and to deal with those and respond accordingly," Sutherland said.

Sutherland stopped short of declaring the Australians had cheated, rather admitting it was a "very sad" day.

"I will make a judgement on that in the next couple of days Let's put ourselves in a position of understanding the fact," he said.

"We regard this as an extremely serious issue. Australian cricket fans want to be proud of their cricket team ... I think this morning they have every reason to not wake up and be proud of the team. It's a very sad day for Australian cricket. One of the very unique things about cricket is that it is not only to be played within the laws of the game but in the spirit of the game.

"Activities on the field yesterday in Cape Town are neither within the laws of the game or within the spirit of the game. For us, at Cricket Australia it is extremely disappointing but, more importantly for Australian cricket fans, it is extremely disappointing as well."

Bancroft has been charged by match referee Andy Pycroft and faces a one-Test suspension, while the reputation of Smith and the Australian team has been shredded.

CA chairman David Peever was on a flight home, having attended the opening days of the Newlands Test.

The cricketing world has reacted in anger and shame, with former England captain Michael Vaughan declaring on social media that "his Team & ALL the management will have to accept that whatever happens in their careers they will all be known for trying to CHEAT the game".

Smith said he would not step down from the captaincy but admitted he and fellow senior players had devised the plan in a bid to extra reverse swing. This type of swing has been pivotal through the series, with the ball going "Irish" after about 40 overs, but the tourists had been unable to extract the swing they had wanted on day three. The Proteas took charge of the Test and have a 294-run lead with five second-innings left with two days remaining.

"The leadership group knew about it. We spoke about it at lunch," Smith said.

"I'm not proud of what's happened. It's not within the spirit of the game. My integrity, the team's integrity, the leadership group's integrity has come into question and rightfully so."

Bancroft said it was yellow tape and not sandpaper that he had taken onto the field.

This story first appeared on The Sydney Morning Herald