* Bok wing Dyanti scores opening try after 25 seconds
* Australia lose fourth game out of five this season
* Boks led 20-12 at break as Australia kept scoreless in second half (adds quotes, details)
PORT ELIZABETH, South Africa, Sept 29 (Reuters) - Wing Aphiwe Dyantyi scored a try in the opening 25 seconds as South Africa kept up their Rugby Championship momentum with a 23-12 victory over Australia at the Nelson Mandela Bay Stadium on Saturday.
The Springboks dominated the early part of the game, but then had to weather a ferocious assault from Australia, who were seeking a first victory on South African soil since 2011 but were let down by numerous handling errors.
Scrumhalf Faf de Klerk also scored a try for the Boks and flyhalf Handre Pollard kicked two conversions and three penalties as the South Africans backed up their stunning 36-34 victory in New Zealand a fortnight ago with another win.
Australia’s tries came via centre Reece Hodge and scrumhalf Will Genia, but despite seeing much of the ball, they lacked an incisive edge in attack and slipped to a fourth defeat in five games in the competition.
“We took our foot off the pedal after a good start,” Bok captain Siya Kolisi said at the post-match presentation. “We have got to be more patient when we get to the 22. There is a lot more for us to improve on before we get better.
“But we will always take a win, the guts and stuff that doesn’t require talent, we showed that. We defended for so long.
“We didn’t have enough ball, but we scrapped until the end.”
The Boks grabbed their opening try from the kickoff as Australia flyhalf Kurtley Beale tried an ambitious skip-pass on his own tryline and Dyanti was able to collect and score.
The Boks added a second try when Pollard slipped the tackle off hooker Folau Fainga’a and set De Klerk away to canter over.
But from their first meaningful attack in the Bok 22, Hodge slid home in the corner for the visitors after a fine skip-pass from Genia.
They had a second score minutes later as an exchange of passes between wing Marika Koroibete and Genia saw the latter run in.
Two Pollard penalties extended the home advantage to 20-12 at the break, before the number 10 added another early in the second period.
Australia dominated after that and when referee Jerome Garcia ran out of patience with repeated infringements from the home side, Dyanti was sent to the sin-bin just past the hour-mark.
But the home side fought bravely on defence and kept the Australians scoreless for the remainder of the game to secure a scrappy victory.
“I’m proud of our guys, they were a bit down after a shaky start,” Australia captain Michael Hooper said.
“South Africa put us under a lot of pressure early. There was a lot of running rugby and it was a good test match, just not the result we wanted.
“We pushed hard to get the yellow card (for Dyanti) and when we got it, we needed to capitalise and we couldn’t do that. It was a brilliant defensive performance from the South Africans.” (Reporting By Nick Said, editing by Pritha Sarkar, Neville Dalton)