Then rugby's image was closely identified with militant Afrikaanerdom and apartheid - more sjambok than Springbok. Even if the game had been acceptable to black opinion, there was no chance to play.
Rugby remains predominantly white. The best black sporting talent is more likely to gravitate to soccer clubs like the Orlando Pirates or the Kaizer Chiefs. But the huge wave of interest in the World Cup, heightened by tomorrow's final clash between South Africa and the All Blacks in Cape Town, has had its impact across all South African communities. The exultant headline in a Soweto newspaper after the Springboks beat Australia - "Amabokoboko", adapted from a soccer chant - is symbolic.
The Springbok slogan "One team, one country", the endorsements of President Mandela and Archbishop Tutu and the visits by competing teams to the townships have all prepared the way for black support of the game. But Joseph Ngobani's hopes are based upon the less publicised, longer-term work started in the Johannesburg township of Alexandra two years ago.
You can't really call it grass-roots sport. Grass is a distinct rarity in Alexandra. But for the past two years something close to rugby has been played in the dirt and concrete yards of the district's primary schools. Mini-league, a 10-a-side game for both sexes, is described as "a foundation sports that imparts ball handling, co-ordination and teamwork skills . . . introducing the fundamental skills found in many team sports."
Introduced by development officer Dave Southern, from Widnes, Cheshire, the game acknowledges kinship with mini-versions of both rugby codes. And it has been seized upon eagerly by children who spend their lives in the hugely overcrowded tin shacks of Alexandra - one of the most deprived areas in South Africa.
A squad of mini-league coaches has been trained by Mr Southern, most of them women teachers like Lucky Mashigo, who teaches English at Gordon primary. She says that both girls and boys love the game. "As soon as you tell them what to do, they follow and don't need to be told again." Her colleague Henry Zakhele Khoza says, "It gives us teachers the chance to work together in a team environment with the children."
Mr Southern emphasises that mini-league is good preparation for any sport, although it has inevitably stimulated interested in rugby. "The skills they learn are as applicable to soccer, netball or basketball."
At Iphutheng school, where the shacks press against the school fence, Joseph suddenly loses his reticence as he confides his ambition. "I had no chance to play rugby before and I love playing. When I grow up I want to be a Springbok and play in the World Cup."
Joseph's teacher, Doctor Pitsi, said: "It gives us a chance to involve the children in sports and keep them away from the street."
Thirteen schools and around 700 pupils aged between five and 13 took part in the first year of the project. A parallel programme has been set up in Sebokeng township, around 100 miles from Johannesburg. Demand appears almost infinite but finding resources to satisfy it is another matter. Mr Southern says, "We don't want to play numbers games, but to ensure that every school involved gets real help. While other sports ask for floodlights, pavilions and tracks, we ask for second-hand kit and equipment," he says.
Companies keen to be involved in improving township life have given financial support. A promising partnership is evolving with mini-cricket organisers.
But there is nothing from the most likely sporting benificiaries, the Transvaal rugby union. Initially helpful - a letter from former Springbok captain Avril Malan is in the first mini league brochure - they have since withdrawn support. Suspicion of the word "league" and Southern's past involvement in rugby league may have been influential factors.
Mini-league South Africa, PO Box 860, Houghton 2041, Johannesburg, South Africa.