For former Australia cricket captain Steve Smith, it was reality television at its most heart-wrenchingly real.

Having lost the captaincy after a ball-tampering scandal in South Africa, Smith returned to Australia on Thursday night and broke down several times in nationally-televised news conference at Sydney airport.

Smith started crying as he reflected on the effect his involvement in a ball-tampering plot in the Cape Town test last weekend had on his parents, and he apologized for the pain he's brought onto them and to the Australian public.

In his first public comments following his 12-month ban from the Australian cricket team, Smith took responsibility for the scandal that has rocked the sport in Australia.

"I just want to say I'm sorry for the pain that I've brought to Australia and the fans and the public," he said. "It's devastating and I'm truly sorry."

It has been a tumultuous 24 hours for Smith, who left South Africa in disgrace after being sent home by Cricket Australia. At Johannesburg airport, he was led through the international terminal by up to six police and security guards, hearing boos and taunts of "cheater" from a crowd that had gathered at the airport.

Smith and Cameron Bancroft fronted news conferences on opposite sides of Australia, while the third player involved in the controversial ball-tampering scandal in South Africa -- David Warner -- used social media to issue an apology while still in the air.

As Warner arrived in Sydney a few hours later, there was drama across in Johannesburg as Darren Lehmann announced he was quitting as Australia coach on the eve of the fourth and final test against South Africa. Lehmann, who took over as coach in 2013, told a news conference that he'd finished when the series concluded.

Lehmann maintained that he knew nothing of the ball-tampering plans in the third test.

Smith, wearing a sports jacket and drawing deep breaths as he spoke, addressed the fans and the children of Australia who wanted to know why he'd cheated.

"Firstly. I'm deeply sorry. I love the game of cricket. I love kids wanting to play the great game of cricket that I love," he said. "Any time you're thinking of making a questionable decision. Think about who you're affecting."

"You're affecting your parents. To see the way my old man has been ...," Smith, stopping briefly to cry, continued. "... and my mum. It hurts."

Smith said as the captain of the Australian team, he had to "take full responsibility."

"I made a serious error of judgment and I know and understand the consequences," he said. "It was a failure of my leadership. I will do everything I can to make up for my mistake and the damage it has caused. If any good can come from this, then I hope I can be a force for change.

"I will regret this for the rest of my life, I am absolutely gutted, I hope in time I can earn back respect and forgiveness."

Nearly 4,000 kilometres (2,500 miles) west, an emotional Bancroft apologized at Perth, Western Australia and said he will forever regret his role in the episode that resulted in 12-month bans for team leaders Smith and Warner and a nine-month ban for him.

"Not a second has gone by when I wish I could turn back time. It is something I will regret for the rest of my life," Bancroft said. "All I can do in the short term is to ask for forgiveness."

Bancroft has only played eight tests since replacing Matt Renshaw in the Australian lineup. Now Renshaw has been recalled to replace him.

"The thing that breaks my heart is that I have given up my spot in the team for free," he said, holding back tears. "People know I worked so hard to get to this point in my career and to have given up that chance is devastating."

A Cricket Australia investigator found that Warner instructed Bancroft how to carry out the tampering with a piece of sandpaper during a break in play on the third day of the third cricket test against South Africa.

Bancroft initially claimed he'd used adhesive tape and dirt to attempt to alter the shape of the ball. It was later proved he'd used sandpaper.

"I lied about the sandpaper," Bancroft explained. "I panicked in that situation. I'm embarrassed by that. I have never ever been involved in tampering with the ball."

English county side Somerset said Thursday that Bancroft would not be its overseas player for the coming season because of his involvement in the ball-tampering scandal.

Warner, who has lost two sponsors already, posted a statement on Twitter and Instagram to say he is on his way back to Australia from South Africa and added: "You will hear from me in a few days."

"Mistakes have been made which have damaged cricket. I apologize for my part and take responsibility for it," he said. "I understand the distress this has caused the sport and its fans."

When he landed late with his wife and two children, Warner said his priority was to "get these kids in bed, rest up, and let my mind be clear so I can talk to you in a couple of days"

"As you can understand, it's been a tough and emotional time."

Smith and Warner were banned from playing any high level cricket in Australia for a year. They've also been barred by Indian authorities from the lucrative IPL.

Smith won't be considered eligible to regain the test captaincy for at least two years, Cricket Australia said. Warner will never again be considered for a leadership role in an Australian team.

Sporting goods company ASICS scrapped sponsorship deals Warner and Bancroft. Electronics company LG on Wednesday said it would not renew its soon-to-expire deal with Warner.

Cereal company Sanitarium on Thursday said it was ending its relationship with Smith.

Reports in the Australia media estimate the suspensions could cost Smith and Warner 5 million Australian dollars (US$3.8 million) each in lost earnings and endorsements.

The Australia Cricketers' Association has foreshadowed potential appeals by the banned players, saying "there are a number of glaring and clear anomalies in the process to date which causes the ACA to query the severity and proportionality of the proposed sanctions."