Embattled All Blacks coach Ian Foster has urged his players to move on quickly from their Mbombela mauling and focus only on the rematch with South Africa at Ellis Park this weekend.

The All Blacks' 26-10 defeat in the Rugby Championship opener was their worst result in 94 years in South Africa, triggering fresh calls in New Zealand for Foster to be sacked.

The three-time world champions have now slumped to a record low of fifth in the world rankings and head to Johannesburg after a fifth defeat in six tests.

With another loss to the Springboks on Saturday widely expected to make Foster's position untenable, the coach said players and staff needed to take a deep breath.

"We know there's a lot of pressure on, and we’re feeling that. But our job is to look at our performance and how we can grow it," he told New Zealand media.

"I understand the frustration, but that doesn’t change what we have to do here.

"There’s no point sulking about it for too long. We’ve just got to get into Ellis Park and keep growing our game and still believe."

Many in New Zealand no longer believe in the team under Foster.

In a front page editorial on Monday the New Zealand Herald, the country's largest newspaper, said Foster needed to go, calling him a "decent man who is out of his depth in a brutal business".

Foster's hopes of rallying his team at Ellis Park appear bleak with injury concerns over flyhalf Beauden Barrett and his fullback brother Jordie.

Kurt-Lee Arendse

Beauden has a sore neck after landing heavily from a mid-air tackle by South Africa winger Kurt-Lee Arendse, who was red carded for the rash challenge, while Jordie left the field with an ankle injury.

Arendse was today suspended for four weeks for the sending off.

He pled guilty to the charge, with a SANZAAR release saying the act of foul play was "reckless, highly dangerous and had a considerable impact on the victim player", and will miss the Springboks' next four matches, but will be available for the home clash against Argentina on 24 September.

It poses a problem for the Boks on the right wing, with Cheslin Kolbe and Sbu Nkosi both out injured.

Coach Jacques Nienaber will name his side for the weekend clash on Tuesday.

Foster complained that Arendse had also clattered into Jordie unfairly as the All Black rose for a box kick in the 11th minute. Barrett was instead penalised for a knock-on.

Foster confirmed the All Blacks would be addressing South Africa's mid-air challenges with officials and said he expected more protection from them.

"It’s becoming a free-for-all for jumpers just to be able to jump and stick a hand out and say they’re competing. It needs to be addressed," he said.