Australian opening batsman Cameron Bancroft landed himself at the centre of a ball-tampering controversy on Saturday when he was caught on camera appearing to hide a foreign object down his trousers, moments before the umpires came to question him about working on the ball.

Fielding in the third Test against South Africa in Cape Town, Bancroft was seen rubbing his hands over the ball shortly before tea on Saturday.

As English umpires Nigel Llong and Richard Illingworth met mid-pitch to discuss the incident, Bancroft was then seen appearing to take a small, yellow object out of his pocket and drop it down his trousers, reports The Telegraph

When questioned by the umpires, Bancroft pulled a black sunglasses cover out of his pocket.

Llong and Illingworth opted not to change the ball or penalise Australia five runs, which is the statutory on-field penalty for illegally changing the condition of the ball. Match referee Andy Pycroft is expected to scrutinise footage of the episode after the close of play.

‘It is very suspicious. There is no doubt about that,’ said former Australia captain Allan Border, commentating on Supersport. ‘If you’re caught doing the wrong thing, you’ve got to pay the penalty.’

Fellow commentator Shane Warne added: ‘You’ve got to own up and say what was it that you were hiding. You can’t have that in the game. We’ve got to get to the bottom of it.

‘The Aussies have to be honest and say ‘this is how it happened’. I don’t have any issue with anyone if they are sucking on a mint or chewing some gum, then that’s just natural saliva.

‘But if you use a foreign object and it tampers with the ball then that has to be seriously looked at. Let’s get to the bottom of what it is and how did it happen. And it’s not fair to nail Cameron Bancroft on it either. I don’t think he would have made that decision by himself.

‘We’ve got to get to the bottom of it. You know when you get caught you’ve got to own up and be honest. The Aussies have to be honest and say this is how it happened.’

Former South Africa captain Graeme Smith said: ‘In my opinion I think he’s tampered with the ball and used an object to do that. It does look like it’s a bit of sandpaper.

‘The footage doesn’t look good. I’m quite amazed the umpires haven’t done anything with the ball. The footage is quite damning.

‘If it is proved that what has gone on in the footage is correct then some tough questions have to be asked of Steve Smith and Darren Lehmann.

‘I think there is a lot of questions that need to be answered and Australia need to answer them. For me it’s quite obvious that he’s doing something with the ball and the umpires need to do something about it.’

The Bancroft incident is the latest in a string of contentious moments throughout the series.

Australia coach Darren Lehmann confirmed on Friday that his side had lodged an official complaint over what he deemed to be abusive behaviour of home fans in Cape Town.

Lehmann said a number of Australian players were subjected to ‘disgraceful’ verbal abuse from fans, including references to players’ families, leading to Cricket South Africa ordering an increased security presence in the crowd on Saturday.

David Warner has become a target for extra attention from home fans after his confrontation with South Africa’s Quinton de Kock on a stadium staircase during the first Test in Durban.

That heated argument, which led to ICC disciplinary hearings and sanctions for both players, was sparked by Warner’s prolonged on-field taunting of De Kock. It resulted in De Kock allegedly retorting with an unsavoury comment about Warner’s wife, and Warner having to be physically restrained by team-mates.