Dubai - South Africa vice-captain AB de Villiers vehemently denied allegations of ball-tampering which led to his team being docked five penalty runs during the second Test against Pakistan on Friday.
Pak v SA Day 3 as it happened
VIDEO: Faf's ball-tampering?
The on-field umpires -- Rod Tucker of Australia and Ian Gould of England along with TV umpire Paul Reiffel of Australia -- intervened when South African fielder Faf du Plessis was allegedly seen rubbing the ball on his trousers, close to a zip, during the third day's play.
Pakistan were 62-5 in the 31st over when the umpires warned South African captain Graeme Smith, changed the ball and handed out a five-run penalty.
As per the ICC (International Cricket Council) rules if the umpires lay charges against the fielder the match referee, David Boon of Australia, can impose a fine of 50 to 100 percent of his match fee or even ban the player.
But De Villiers stressed South Africans don't cheat.
"Honestly, we're not the team that scratches the ball," said De Villiers.
"We play in a fair manner. Obviously we want to swing the ball as much as you can and try to get it to reverse. We don't cheat, it's as simple as that," said De Villiers, who backed Du Plessis.
"I know 'Faffy' very well, he's the last man to try anything like that, it is part of his responsibility to shine the ball and I thought he did it very well."
De Villiers was surprised how events unfolded on a day when his team had taken a firm grip on the match and were heading for a series-levelling win.
"Honestly, I don't know what happened there, I don't even know from where the message came. Obviously very surprised, there was no talk about it, no warnings, nothing. It was just out of nowhere."
The ball-tampering controversy aside, South Africa have dominated the match and will look to force a thumping victory on Saturday.
Pakistan, who won the first Test, finished the third day on 132-4, still 286 runs behind and facing an innings defeat.
South Africa were bowled out for 517 with Smith hitting a memorable 234 and De Villiers 164 to pile-up a huge 418-run first innings lead.
"We definitely are in a strong position to win this Test, another 300 runs with four down and the new ball is just around the corner," he said.
"To get four down on a wicket that is still playing well, it's set up nicely, we just need to be patient tomorrow, work really hard to get wicket number five and get the wicketkeeper in and then the tail," said De Villiers.
De Villiers added he was proud of his partnership with Smith.
"That was very enjoyable, we have batted together quite a few times, being opening partners a while ago.
"It's very nice to bat with him. He has got a great presence at the crease and there is a nice atmosphere, not too serious, and it was good," said De Villiers of the 338-run partnership, an all-time South African record for the fifth wicket.