MELBOURNE, Nov 12 - Cricket Australia chairman David Boon has backed test captain Pat Cummins and said his job is not under threat over the allegations in Usman Khawaja's book about his role in the 2018 ball-tampering affair.

Former test batter Khawaja’s assertions that he and all of his teammates on the tour of South Africa had prior knowledge of a plan to manipulate the ball has reopened old wounds and triggered calls for another investigation.

The saga has heaped fresh scrutiny on Cummins as the current leader of the test team, with pundits calling on him to respond to the allegations.

Boon said Cricket Australia (CA) had full confidence in Cummins' leadership as a player of integrity.

“We absolutely support Pat,” Boon said in comments published by The Australian on Thursday.

“He’s been an exemplary captain, he’s led the team with integrity and, you know, very successfully over the period of time that he’s been captain, so there’s no question of our confidence in him continuing on in that fact.”

Cummins has yet to respond to Khawaja's allegations but posted on X that he would be happy to speak to media on Friday.

"I've taken some time to try and better understand the long list and full extent of Uzzy's allegations so I can respond properly," he wrote.

White-ball captain Mitchell Marsh, who was in the test team in 2018, will speak at a press conference in Perth later on Thursday ahead of a one-day international against England.

Khawaja's allegations were backed to the hilt by former teammate David Warner, who, along with Steve Smith and Cameron Bancroft, was banned for his part in the ball-tampering scandal.

Former test bowler Chadd Sayers, who was also on the 2018 tour, also said Khawaja's allegations were "accurate" in comments to Australian media last weekend.

However, CA CEO Todd Greenberg said on Tuesday there was no compelling reason to reopen the case and Boon reiterated that stance.

"I respect (Usman’s) point of view and his recollections of what occurred, and they’re his, but we don’t want to get into a he-said-she-said argument," he said.

"There are going to be supporters, there’s going to be other guys that don’t recollect the same thing, so I don’t see a purpose.”

Khawaja said in his autobiography "Sabr", released this week, that Australia had been ball-tampering in the second test in South Africa, and not just at the third in Cape Town.

Former Australia batting coach Graeme Hick dismissed Khawaja's remarks as "absolutely false".

"In regard to any discussions around the ball-tampering in Port Elizabeth or Cape Town that took place, I will say in true honesty that I did not hear or know anything," he told the Sydney Morning Herald.

Fast bowler Mitchell Starc also denied on Tuesday prior knowledge of the ball-tampering.

Starc and fellow bowlers Cummins, Josh Hazlewood and Nathan Lyon issued a joint statement in 2021 saying they did not know a "foreign substance" had been taken on the field to manipulate the ball in Cape Town. REUTERS