Ardie Savea says he backs "my coach" Ian Foster "100 per cent" after New Zealand lifted the gloom with a magnificent 35-23 win over South Africa on Saturday.

Foster may still lose his job as All Blacks head coach despite a thrilling Rugby Championship victory at Ellis Park.

New Zealand opened up a 15-0 lead in the first half, but the world champions came storming back and were in front for the first time with 12 minutes to play.

With Beauden Barrett in the sin bin it looked like the Springboks would extend the All Blacks' losing streak to four matches, but late tries from David Havili and Scott Barrett ensured they stopped the rot and lifted the Freedom Cup.

Foster said he has no idea if he will remain in his role despite the much-needed win, but Savea - who was immense in Johannesburg - is fully behind his embattled head coach.

"This performance was for all of us, but for me, that's my coach, I back him 100 per cent, side by side," said the number eight, who made 13 carries for 58 metres.

"He has been under a lot of pressure, and I know Foz [Foster] doesn't want to make it about himself, but I just want everyone to know that all the players have got his back.

"He's a great coach, he's got great coaches beside him, and we back him 100 per cent. I hope everyone that reads this backs us because we are going to get it."

Asked if Foster deserves to stay on, Savea replied: "Like I said, he's my coach. That's it."

Freedom Cup pic.twitter.com/uhDVWm5xJO
— All Blacks (@AllBlacks) August 13, 2022

Captain Sam Cane and Samisoni Taukei'aho crossed in the first half, while Richie Mo'unga scored 15 points with the boot for the holders

Savea expressed his pride following another almighty battle at the end of a challenging week.

"The last couple of weeks this team has been through adversity, and in life and sport when you go through adversity it brings the best out of people," he said.

"I saw something saying belief only takes us so far … it took us pretty far this week. I'm just proud of everyone in this team stepping up, especially at Ellis Park. It's bloody hard, I'm knackered, and can't wait to hit the sack and go see the family next week."

He added: "There are always doubters, always negativity, but that's okay, because that makes everyone better, and people care. Our fans care, the media care, which is fair, but also we had to step up and do our job.

"When people go through adversity, when they're stuck in the trenches, some things come out that make us special. Today that was it, but it's only a start. We've won one out of two in the Rugby Championship, and we’ve got to keep going."