Darren Lehmann will continue as Australia coach but the futures of skipper Steve Smith and vice-captain David Warner remain unclear after they were warned they face “significant sanctions”.

A Cricket Australia investigation found that Lehmann had no prior knowledge of the plan to tamper with the condition of the ball during the third Test against South Africa in Cape Town.

CA chief executive James Sutherland said that Smith and Warner were the only members of the set-up aware of Cameron Bancroft’s attempt to manipulate the ball with sticky tape against the Proteas.

“I want to apologise to all Australians for what took place,” Sutherland told a press conference in Johannesburg.

“It’s about the reputation and integrity of Australian cricket and Australian sport and whether Australians can take pride in their national team.

“The key finding is that prior knowledge of the ball-tampering incident was limited to three players – captain Steve Smith, vice-captain David Warner and Cameron Bancroft.

“No other players or support staff had prior knowledge and this includes Darren Lehmann, who despite inaccurate media reports has not resigned from his position. He will continue to coach the Australia men’s team under his current contract.

“The three players on report, we are contemplating significant sanctions, which will reflect the gravity of what has occurred and the damage it has done to the standing of Australian cricket.”

All three players involved have been sent home ahead of the fourth and final Test in Johannesburg, which the tourists must win to square the series, with Matt Renshaw, Glenn Maxwell and Joe Burns called up as replacements.

Tim Paine, who took over from Smith as captain mid-match in Cape Town as the furore began to unfold, has been appointed as captain of the Test team.

Cricket Australia chairman David Peever said in a statement: “We understand and share the anger of fans and the broader Australian community about the events that unfolded in Cape Town on Saturday.

“Ultimately, it is about whether Australians can feel proud of their national sporting teams.

“That depends as much on the way the players conduct themselves as it does about winning or losing. It is about how we play the game.”

Sutherland revealed that Smith – who was already unavailable for the fourth Test after being handed a one-Test ban by the International Cricket Council – Warner and Bancroft can expect to learn their fates on Thursday.

“I fully understand the wish for urgency, however urgency must be balanced with due process,” he added.

“We’ll complete the process by tomorrow morning and in the next 24 hours we’ll be in a position to announce sanctions.

“The feeling from Iain (Roy, Cricket Australia’s head of integrity) in his review is that it’s an isolated incident, but again there are things that I don’t want to go into too much detail around right now.

“I certainly hope it’s an isolated incident, but it’s certainly one of significant concern.

“This is not in the laws of the game, it is not in the spirit of game and I am angry and disappointed. It is not a good day for Australian cricket.”

He added: “In addition to the sanctions for individuals, Cricket Australia will take the opportunity to review the conduct and culture of our professional teams.”