You walk out in a Springbok jersey as a player and you feel history on your back and by your side.

You stand as South Africa's captain in a World Cup final and the weight is greater across your shoulders and the ghosts crowd in all around.

Francois Pienaar hoisting the Webb Ellis Cup at Ellis Park in 1995, Nelson Mandela alongside him in his own green number six jersey, happy like a kid who has just scored his first try. John Smit at the Stade de France in Paris 12 years on, left hand around the old gold pot, right hand linked with Mandela's successor Thabo Mbeki.

Twelve years more have passed. Now it is the turn of Siya Kolisi to walk that path. The first black man to captain the Springboks, a kid from nowhere who hopes to go where none have gone before.

Rugby matters in many places around the world, but only in South Africa can it change the nation around it. Captains and presidents, politics and power, new dreams and old scars.

"It was iconic when Francois lifted the World Cup with Madiba, and it was amazing to be able to do it myself with Thabo," says Smit.

"But if Siya touches that trophy on Saturday... I tell you, it will be a far greater moment than 1995. Far greater. It would change the trajectory of our country."

That Kolisi has made it this far is a story of stoicism and self-belief. Born to teenage parents in the poor township of Zwide, just outside Port Elizabeth on the Eastern Cape, he was brought up by his grandmother, who cleaned kitchens to make ends meet.

Bed was a pile of cushions on the living-room floor. Rugby was on dirt fields. When he went to his first provincial trials he played in boxer shorts, because he had no other kit.

His father Fezakel was a centre, his grandfather a player of pace too. Aged 12, the young Kolisi was spotted by Andrew Hayidakis, a coach at the exclusive private school Grey, and offered a full scholarship.

When you are from Zwide you step into this other world when the chance comes, but you never leave your old life behind. Kolisi's mother died when he was 15, his grandmother shortly afterwards. When Smit's team was beating England in that World Cup final of 2007, the 16-year-old Kolisi was watching it in a township tavern because there was no television at home.

"His story is unique," Hanyani Shimange, former Springboks prop, told BBC Radio 5 Live's Rugby Union Weekly podcast.

"Previous generations of black rugby players were not given the same opportunities, purely because of South Africa's laws. He's living the dream of people who weren't given the same opportunities as him.

"He's grabbed those opportunities. He's a good man, a humble individual.

"He's got a lot of time for people, probably too much time in some instances. But he's the same Siya he was six years ago. He loves rugby, and the team loves him."

Kolisi began at school as a small but mobile flanker, good with the ball in hand, learning to be smarter than the stronger kids around him. When a growth spurt kicked in and he got big there was power to go with the finesse.

As a loose forward he is a significant asset to a Springbok team that at this World Cup has battled through to the final rather than dazzled. Saturday will bring his 50th cap, and his 20th as captain. His impact is far greater than simply what he does on the pitch because of all that has come before.

"I do not care how the Springboks team does. It is not a reflection of the nation. It is not our team. I support the All Blacks instead. We don't support the national team, because it is a white South African team. It is not a true South African team."

That was Zola Ntlokoma, secretary of Soweto Rugby Club, talking to me before England played South Africa at Twickenham five years ago. It was not an uncommon view, because for all the iconography and sweet symmetry of 1995, its wider effect quickly leached away.

Integration of black players crawled along rather than accelerated. The World Cup win gave the impression that little more needed doing, and so little was.

When the Springboks triumphed in Johannesburg 24 years ago there was just one black player, Chester Williams, in the starting XV. By the time of their second World Cup win in 2007, there were still only two.

In some corners of South African life, the story of 1995 feels old and frayed. When Williams wrote his autobiography he accused fellow winger James Small of using racially abusive language towards him in a domestic cup match after that World Cup win. Small, who said he had "no independent recollection of the incident", in turn felt an outsider even in victory because his native tongue was English rather than Afrikaans.

Small - often angry at the world, brilliant at his best, the man who helped keep Jonah Lomu tryless in that final - died of a heart attack aged 50 in June this year. Williams went the same way last month aged 49, the fourth player from that storied team - after flanker Ruben Kruger and virtuoso scrum-half Joost van der Westhuizen - to go at an untimely age.

Kolisi stands as a critical link between the past and future. He was born on 16 June 1991, one day before the repeal of apartheid - brutal laws that enforced discrimination against black people in every aspect of their lives. Separate land. Separate public transport. Separate schools.

Kolisi was there at Small's funeral. Williams' image was on the shirts his team wore for their World Cup opener against the All Blacks. In Kolisi's team, the legacy of that old generation is tangible.

In the starting XV that beat Wales in Sunday's semi-final there were six black players: wingers S'busiso Nkosi and Makazole Mapimpi, centre Lukhanyo Am, prop Tendai Mtawarira, hooker Bongi Mbonambi, and Kolisi. Of Rassie Erasmus's squad of 31, 11 are black.

The lesson of 1995 was that transformation is more complicated than a single iconic image. The challenge that lies for the next group of players and administrators will be to create a wider pathway from undernourished grassroots to the elite.

Picking up occasional gems has worked. Kolisi made the jump. Mapimpi is also from the Eastern Cape, and did not go through the private school system. He still made it. There are other black kids, those who don't get the scholarships or find the eyes of a roving talent scout, who are still slipping through the net.

"If Mapimpi hadn't been in an area where rugby is strong and he was given the chance to play and be signed by other teams, the chances are we would never have seen him," says Shimange.

"It would have taken someone to go and scout him and spot the talent in him and then give him the chance to perform at the highest level.

"But we had generations of people who couldn't play for the Springboks, who weren't allowed to watch the Springboks, and now you have Siya running out there with his 15 men.

"Even the thought is incredible. It's why the most important person for the country for those 80 minutes on Saturday is going to be Siya Kolisi."

Back in Zwide, preparations are ongoing for a weekend of World Cup parties. The tavern where the teenage Kolisi watched his first final will be open once again. The skipper is only 28, but already he is changing his old home forever.

"During the apartheid time, we could never look forward to a moment like this, because of our colour," says Freddie Makoki, president of Zwide United rugby club, who played with Kolisi's father and grandfather and watched the young Siya grow.

"We had so many players who could have captained the Springboks, but because of their colour they couldn't.

"Sport can bring people together in this country. There are places you can't walk at night, because of criminals. Sport is the only vehicle that can change that. If you take those boys and put them in sport it can change them and it can change our society.

"Siya has been an incredible role model for children here. Whenever he comes to visit you'll see the youngsters coming out to see him. Everyone in the townships wants to be closer to him.

"He is a son of our soil. If you could have seen how full the taverns were for the semi-final you would not believe it. All of these people are now supporting the Springboks.

"It makes me so proud to see him in the Springbok jersey, to see the crowds at the game, calling out 'Siya! Siya!'

"You can see it in the faces of the people of this country how much it meant to have Siya as captain. He is a true hero of modern South Africa."

Kolisi's father is flying out to Japan to watch the biggest game of his son's life. It is his first trip overseas.

So too is the country's president. Cyril Ramaphosa called Kolisi on FaceTime after the win over Wales. Now he is coming in person. Captains and presidents, politics and power.

"Siya has more responsibility than I did or Francois did because he represents more people," says Smit, who will also be in the Yokohama stadium, this time for SuperSport TV.

"Thanks to Madiba, Springbok rugby has been used almost in the opposite way to how it was used in the apartheid era. It's a team that has been able to bring people together. It's grown the country through its ability to win.

"That's the hard thing to explain to people outside South Africa - what a Springbok win in a World Cup has done in the past for unification, and us continuing on this road to democracy and a new pathway.

"That's how important this is. Siya's story about where he's come from shows how far the country has come."

And so Kolisi carries that weight on his shoulders. Dreams and messy pasts, old heroes and deep-rooted struggles.

Only a game, but so much more too. Ghosts all around him, a new future ahead.

"I will be wearing my Springbok jersey," says 68-year-old Makoki, whose own career in the game was stunted by apartheid, who watched local heroes rise and fall short, who continues to nurse the sport in Zwide township.

"I'll be thinking about going to OR Tambo airport when they come back with that trophy. If I can be one of those people there to welcome them back I will be truly happy.

"When the Springboks won that World Cup in 1995, it brought South Africa together. But this would be more, because we have a lot of players who are knocking at the Springbok door. We'd have a lot more black players playing rugby again.

"I'm telling you! It will be more, it will be more.

"A black president and black captain, from a small town on the Eastern Cape. I'm telling you - that can save our country."