Willemse - only black player in the squad (Getty Images).

By Alex Lowe, PA Sport, Melbourne

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A new race row threatens to overshadow the Springboks' biggest game in four years after South African Rugby Union boss Mvuleli Ncula voiced concerns that the side selected to take on the All Blacks is too white.

Following the collapse of apartheid, South African rugby has employed a provincial quota system aimed at helping talented black youngsters develop into international standard players.

Although that quota system does not apply to the Springboks, Nvcula has been quoted as saying he is concerned that Rudolf Straeuli's selection is a backward step for South African rugby.

Star winger Ashwin Willemse is the only black player in the 22-man squad that will take on New Zealand in the World Cup quarter-final on Saturday.

"At the 1995 World Cup we had only one black player (Chester Williams) on the field and it was the same in 1999 when there was never more than one black player in the team (Breyton Paulse or Deon Kayser)," Ncula is quoted as saying by the Pretoria News.

"Now we have only one black player in the match 22; if Willemse gets injured, we have an all-white team.

"Everyone in South African rugby must take the blame."

Ncula reportedly said that black South Africans were beginning to question what progress had been made despite an alleged 100million Rand investment.

The last time Ncula spoke out over Straeuli's selection policy was after prop Lawrence Sephaka was replaced by Christo Bezuidenhout for the crunch Pool C game against England.

"This could take us back years. Before the World Cup started the ANC Youth League came out in support of the team, but the moment Sephaka was dropped they turned against us," Ncula told the Daily News.

"It is not specifically about Sephaka being dropped. It is because there are so few black players in the squad."

SA Rugby boss Rian Oberholzer had initially demanded Straeuli select at least six black players in the 30-man World Cup squad.

They arrived in Australia with five - Willemse, Sephaka, Breyton Paulse, Ricardo Loubscher and Dale Santon - after centre Gcobani Bobo withdrew with a knee injury.

All have featured during the World Cup, though Willemse will be the only one to have started in the key games against England, Samoa and in tomorrow's quarter-final.

"Everyone in South African rugby must take the blame, including provincial coaches," said Ncula.

"Most of them only stuck to the minimum requirements of three black players in their match 22s and two on the field at all times.

"The exceptions were Free State, Border, Eastern Province, Boland and South Western Districts, the best of the bunch with around six in their team."

Ncula said the loss of star flanker Joe van Niekerk was the ideal time to fly over a rising black loose forward.

"We applauded the Boks when they called up a good young player like Schalk Burger," he added.

"But we have to ask then why can't the same be done with someone like (Eagles flanker) Kabamba Floors or (Sharks flanker) Solly Tyibilika?

"Both of these players were only really discovered in this year's Currie Cup. But after Joe van Niekerk fell out of the World Cup with his injury, there was an opportunity for one of them to go over to the World Cup, even if it was only for the experience."

Danie Rossouw was named as Van Niekerk's replacement at loose forward.

No-one from the Springboks' World Cup camp was initially available for comment.