The South African camp has rallied round hooker Bongi Mbonambi who has been accused of making a racial slur at England's Tom Curry, saying he was a "humble guy" and a "human guy".

Mbonambi, 32, would be a huge loss to the defending champions for Saturday's final with fellow three-time winners New Zealand if World Rugby's investigation finds him guilty.

He has made light of the absence of fellow 2019 World Cup-winning hooker Malcom Marx, who had to leave the tournament due to injury, and was named man of the match in the 29-28 quarter-final victory over hosts France.

Curry made the accusation when he approached match referee Ben O'Keeffe after half an hour of Saturday's hard-fought semi-final which the Springboks won 16-15.

However, although South Africa defence coach Daan Human would not address the accusation directly, he made plain his admiration and respect for Mbonambi, who has also assumed the captaincy role when Siya Kolisi has gone off.

"It's being dealt with by World Rugby and South Africa Rugby at the moment," he told reporters.

"From our side I really can't comment on something like that.

"Bongi has been part of this group for the last six years. He is a very important piece of our puzzle, he is definitely very important to us like all the other players.

"He is definitely one of our leaders in the group as well, a great guy.

"He is a very humble guy, down to earth and a very hard worker like all the other players, which they should be if they want to play for the Springboks."

Human claimed not to have spoken to Mbonambi about Curry's accusation that he called him "a white (followed by an expletive)". 

"To be straightforward and honest with you, he is a calm guy," said Human.

"He is well spoken and I don't want to actually go into it because we have a World Cup final in six days' time."

If Mbonambi were barred from the final, it would leave South Africa short on specialised hookers as Marx was replaced in the squad by fly-half Handre Pollard.

Converted backrow forward Dean Fourie has been Mbonambi's replacement off the bench.

Human dismissed those concerns.

"I can tell you one thing, we have three hookers (including Dean Fourie and Marco van Staden) in the group," he said.

"Three guys who are capable of playing hooker so we are very comfortable having three hookers.

"If you want to go into a final, you must have two hookers."

Springboks lock Jean Kleyn gave the accusation against Mbonambi short shrift.

"Bongi is a great guy, I have known him since we played together at the Stormers," said Kleyn.

"Passionate guy, a family man. He has captained the Springboks a few times now. I don't think there's a fella in the squad who doesn't like him.

"I'm not going to comment on it, I'm not going to justify it."

pi/gj