'It was the only decent rugby we played' - Erasmus fuming over Bok display

South Africa boss Rassie Erasmus expects significant improvements from his team after watching them labour to a 34-21 victory over Argentina in their Rugby Championship opener.

Two tries apiece from Aphiwe Dyantyi and Makazole Mapimpi, together with scores for Lukhanyo Am and Faf de Klerk, saw the Springboks come from behind to get the better of the visitors in Durban.

They could well face a sterner examination on the Pumas' turf in the return fixture next weekend in Mendoza, where Erasmus knows there will be no margin for error.

"The only positive was the first 30 minutes in the second half; it was the only decent rugby we played," he said.

"I was expecting that we wouldn't produce a completely fluent display, but the first half was worse than I thought. Thankfully [captain] Siya [Kolisi] and the boys picked it up after the break.

"We lost a few line-outs that were crucial and there were some technical errors but for all of that it was a dominant performance, but it wasn't the crispest performance. Technically and tactically we weren't on par today."

Asked what he expects of Argentina next weekend, Erasmus replied: "They know what we're about now and we'll make a few changes to the team - four or five changes – as we're expecting a massive physical onslaught; they are fuming.

"They have always been tough there – but we got five points out of this game; not the most beautiful and perfect game but we're well in it. Going there I don't think we have the luxury of experimenting."

Pumas coach Mario Ledesma said: "They kept playing direct physical footie and it's like a dam; if you keep hammering, hammering eventually the wall will break."