The ugly incident at Mbombela Stadium that finished with Beauden Barrett landing heavily on his neck is one of two dangerous high ball challenges the All Blacks are seeking clarification on before attempting to arrest their sustained form slump in South Africa.

Springboks wing Kurt-Lee Arendse received a red card late in the All Blacks' 26-10 defeat after wiping Barrett out in the air while he was attempting to field a high ball.

Scans after the match cleared Barrett of serious neck damage and he did not undergo an HIA assessment. Despite the initial alarm, All Blacks coach Ian Foster is yet to rule Barrett out of the second test at Ellis Park.

"We'll make a decision on that later in the week but he's still a bit sore," Foster said.

Beauden Barrett was taken out in midair by Kurt-Lee Arendse. Photo / Photosport

As the All Blacks departed the secluded Ingwenyama Conference and Sport Resort for Johannesburg's business district, Foster made his feelings on the incident clear when asked if he had concerns about the nature of the challenge.

"Massive concerns," Foster said. It's probably worst I've seen."

Foster also expressed frustrations with a similar incident involving Arendse, who faces a lengthy suspension for his red card, earlier in the match on Jordie Barrett.

"It's pretty disappointing because it happened in the 10th minute as well and they deemed that was fair," Foster said. "That's part of the problem in the game. In the lineout if you throw a jumper over to their side with an arm up it's considered obstruction whereas it's becoming a bit of a free for all for jumpers to jump and stick a hand out and say they're competing, so it needs to be addressed."

The challenge on Jordie Barrett was reviewed at the time by the TMO but Foster now plans to take his concerns to World Rugby officials.

"We've got to make sure we're protecting guys in the air. To be fair if you're going to compete you should at least show a couple of hands up.

"We need to make sure we seek clarification about what we can and can't do particularly with high balls and also with the breakdown, how to move people."

Caleb Clarke talks to an assistant referee in the All Blacks' defeat to South Africa. Photo / Photosport

Jordie Barrett left the field in the second half with an ankle injury that Foster confirmed was "bad" and is therefore likely to rule him out of the second test.

Whether Will Jordan - who was dominated from the right wing in the air by Springboks opposite Makazole Mapimpi - Beauden Barrett or Stephen Perofeta starts at fullback they can expect another aerial assault from the Boks.

With that in mind, Foster is intent on cleaning up challenges in the air to ensure a fair and safe contest for the ball.

The only certainty is the Boks will stick with their kick-heavy tactics that brought success in the form of their opening try to Arendse and several other gains.

"It becomes a lot easier if there's a wide interpretation of what you can do underneath it. We've got to look at our responsibilities in the air and how we catch because it's coming but, by the same token, we do expect more protection than we got."