Ex-teammate's firm defence of Lehmann

Former Australia batsman Jimmy Maher has launched an impassioned defence of under-fire coach Darren Lehmann, saying the ball-tampering scandal goes against his former teammate's morals.

With Cricket Australia stepping up its internal investigation in South Africa, the focus has turned to Lehmann, how much he knew about the plot and his role in attempting to cover it up.

After unconfirmed reports emerged on Tuesday morning that Lehmann was set to resign, Maher went on the front foot to defend his former teammate, who is yet to speak publicly on the matter.

"I want to make it clear from the outset that we're good mates but I would be very, very surprised if Darren Lehmann knew anything about what's happened," Maher told Fox Sports News.

"He's not that sort of person. He doesn't stand for that sort of thing and I'm sure had he known about it he would have stopped it. That's the man I know and I'll be very surprised if I'm proven wrong with that. 

"He's a very proud man, he’s a very loyal man and I know he's done a very good job with the Australian cricket team and I think he'll be gutted by what's happened.

"He will, in some respects, feel that he's responsible, I guess, even though he had no knowledge of it. He'll be gutted by what happened. He's always stood up for his players and I think he's done a very good job since he's been at the helm, performances under him have been very good.

"How he's taking it right now, I'm speculating but he will be taking it hard and I am 100 per cent sure he would have had no knowledge of it."

Maher conceded he believed Lehmann will likely be forced to resign over the affair, but that he shouldn't lose his job particularly if he had no knowledge of the scheme.

It's important to note that in admitting his guilt on Saturday, captain Steve Smith said none of the coaching staff - including Lehmann - were involved in the plot to deliberately tamper with the ball.

But two Test greats, former Australian wicketkeeper Ian Healy and former England captain Nasser Hussain, say the coach is in the firing line whether he knew about the plan or not.

"It doesn't look good on Lehmann either way, really," Hussain told Sky Sports.

"If he did know then he's in a whole heap of trouble and will not be able to hold his job down if he is condoning cheating and scratching of a cricket ball.

"If he didn't know, then questions will be asked as to why senior players are going around not telling the coach exactly what is going on.

"In the dressing rooms I've played in, it is inconceivable that the coach wouldn't know something like this was being dreamt up."

Hussain's claim that Lehmann had to know about the scheme, which Smith said was devised during the lunch break on the third day at Newlands, was strongly denied by Maher.

"This notion that I've heard some commentators and some cricketers say that if it's happening in the dressing room everyone knows about it, that's just absolute BS," Maher said.

"In the dressing room, during a lunch break, there's people everywhere. Some people are getting rubdowns, some batsmen are in the corner having a conversation, the coach could be in the nets, he could be talking to a selector, there's masseurs around, physios ... there's just a lot going on (during) a lunch break in a dressing room.

"It's very, very, very possible that Darren Lehmann was nowhere to be seen when this conversation was taking place between the alleged three players that people have spoken about. So for people saying he had to have known about it is just crazy."

Maher, who played 10 ODIs with Lehmann and shared Australia's 2003 World Cup triumph with him, also defended the coach's silence since the scandal broke on Saturday.

"He has probably been told by Cricket Australia - and I'm almost certain that he would have been - that he's not to comment on anything until the investigation has happened," he said.

"So if that's the case, his hands are tied, he can't come out and say what he wants to say even if he wanted to.

"His name's been thrown around here pretty badly and I'm sure that when the time's right and when he's given that green light, I'm pretty sure he'll give us a very frank and open view on what happened.

"People have got to understand that he's probably been told - no, he's certainly been told - not to say anything until the investigation has been completed.

"So what does he do? He can't just come out and go against those orders if his employer is telling him he's not allowed to speak about it."

Selected players and support staff were interviewed on Monday in Cape Town as Cricket Australia's internal investigation into the ball tampering scandal kicked off.

CA's Head of Integrity Iain Roy has been tasked with carrying out the investigation and conducted interviews at the team hotel, which saw hungry news crews and photographers huddled outside the main entrance for most of the day.

Having flown to South Africa from Melbourne on Monday, CA chief executive James Sutherland will be in Johannesburg when the team arrives on Tuesday night (AEDT) and he will await the findings of the investigation being conducted by CA's Head of Integrity Iain Roy.

CA is aiming to provide an update to the Australian public by Wednesday morning AEDT at the latest.

Qantas tour of South Africa

South Africa squad: Faf du Plessis (c), Hashim Amla, Temba Bavuma, Theunis de Bruyn, Dean Elgar, Heinrich Klaasen, Quinton de Kock, Keshav Maharaj, Aiden Markram, Morne Morkel, Chris Morris, Wiaan Mulder, Lungi Ngidi, Duanne Olivier, Vernon Philander, Kagiso Rabada, AB de Villiers.

Australia squad: Steve Smith, David Warner, Cameron Bancroft, Pat Cummins, Peter Handscomb, Josh Hazlewood, Jon Holland, Usman Khawaja, Nathan Lyon, Mitchell Marsh, Shaun Marsh, Tim Paine, Jhye Richardson, Chadd Sayers, Mitchell Starc.

Warm-up match: Australia beat South Africa A by five wickets. Report, highlights

First Test Australia won by 118 runs. Scorecard

Second Test South Africa won by six wickets. Scorecard

Third Test South Africa won by 322 runs. Scorecard

Fourth Test Wanderers, Johannesburg, March 30-April 3. Live coverage