Hobart, Australia: South Africa insisted a ball-tampering controversy had been "blown out of proportion" on Friday as they kept their focus on a third straight series win in Australia.

Skipper Faf du Plessis was unmoved by accusations of tampering in South Africa's thumping 177-run first Test win, saying Australia also got the ball to reverse-swing.

Du Plessis was warned by the umpires for deliberately bouncing the ball along the ground, to rough it up, but he said there was no unfair advantage.

"I think it's been blown out of proportion. We were watching the first innings in Perth and they (Australia) got the ball to reverse in the 25th over," he said in Hobart, where the second Test starts on Saturday.

"I was quite impressed. I was trying to see how they were doing it because that meant they were doing something right. Twenty-five overs is very early for ball to reverse.

"We are a bowling attack and we enjoy bowling with a swinging ball. To say it was only for us is not true.

"It was 50-50 the amount of reverse swing throughout that Test. The Aussies did it really well."

Reverse swing -- when the ball moves away from its usual trajectory, usually when it is older and rougher -- is unlikely in lush, damp Hobart.

"Perth was really dry and extremely hard. It will be different here," du Plessis said. "It is lush, it's green, it's soft, it's wet. It will seam and swing, but won't reverse that much."

- 'They let it slip' -

The Proteas are on the verge of emulating the intimidating West Indies teams of the 1980-1990s with three straight series wins in Australia after their convincing victory in Perth.

Forecast rain may thwart South Africa's hopes of clinching the three-Test series in Tasmania, but du Plessis says his tourists are in a good space after outplaying Steve Smith's team over four of the five days in Perth.

Du Plessis, deputising for injured skipper AB de Villiers, says he has a team full of resilient characters while Australia will be "hurting" from their fourth straight Test defeat.

South Africa have shown their strength under pressure with series triumphs on their last two trips to Australia in 2008/2009 and 2012. They have lost only one of their last seven Tests in Australia.

"We rely quite heavily on being a resilient team, we're full of resilient players and personalities," du Plessis told reporters at Bellerive Oval.

"Some of the guys are very, very resilient and put their hand up and fight extremely hard to get back into the game. It's always been a strong part of this team," he added.

South Africa fought back after being dismissed for 242 on the first day in Perth to wrest control from the home side and dominate the remainder of the Test.

"If you want to win Test matches you'll get small opportunities in games where it's 50-50, where either you take that pressure and get through that moment to get on top again, or you don't and you fall behind the game," he said.

"Luckily for us in the previous Test match we could do it more than they did. They had that opportunity and they let it slip."

Du Plessis said the contest to replace injured strike bowler Dale Steyn was between Kyle Abbott and Morne Morkel, while the adverse weather forecast could also mean they don't play spinner Keshav Maharaj.

South Africa (from) - Stephen Cook, Dean Elgar, Hashim Amla, Faf du Plessis (capt), Temba Bavuma, JP Duminy, Quinton de Kock, Vernon Philander, Keshav Maharaj, Kagiso Rabada, Morne Morkel, Kyle Abbott