It is four years since South African Chad Le Clos shocked the swimming and sporting world by beating the previously invincible Michael Phelps to win Olympic gold in the 200 metre Butterfly in London 2012.

His father, Bert, also became a media star with his huge support for his son. A war of words with Phelps ensued around last year’s World Championships in Kazan and now they are going to set the record straight in Rio.

Proud family man Le Clos, a humble 24-year-old Olympic, World and Commonwealth Games champion from Durban, reveals the tale behind his journey to the top and how he is going to Brazil in the knowledge both his parents are facing private battles against cancer.

How will you draw on your 2012 race to triumph in Rio?

Everything came together to form a perfect moment on 21 July 2012 and my dream came true. It was a crazy road from being a kid to Olympic gold. Phelps was my hero growing up and unbeaten for a decade. My game plan was to swim like he did and beat Michael Phelps at his own game.

Michael Phelps and Chad Le Clos compete in the men's 200m butterfly final during the swimming event at the London 2012 Olympic Games AFP/Christophe Simon/Getty

I remember feeling really well. I thought I would be a lot more nervous but it didn’t go to plan at first and I was well behind before I had to throw everything at him. It is four years ago, but I can remember like it was yesterday.

What was it like beating your hero?

I’ve looked up to him my whole life and to beat him in the biggest stage at the biggest moment was my dream came true. Then, at the medal ceremony I saw my team mates and coach and began to realise it was even bigger than I ever thought it could be.

What is it like training outdoors in Pinetown, Durban, when Phelps and your rivals have state of the art facilities?

It is not exactly the safest place in world – three of my family’s cars have been stolen from there, but you learn to deal with that side of life. I have been training there for 15 years. I would only give it two or three out of ten, but my dad says it’s the worse pool in the world.

At the end of the day I feel the facilities and hardships have made me who I am.

It has no roof. I feel like if a lot of the Americans and Aussies had the same facilities they would not even make the Olympic Games – I can promise you that.

Chad Le Clos of South Africa speaks to the media during the FINA World Championships at Palau Sant Jordi on July 24, 2013 in Barcelona, Spain © Clive Rose/Getty Images

Does that lack of privilege help or hinder you?

At the end of the day I feel the facilities and hardships have made me who I am. Because of that I am mentally tougher and know when I am on the starting block I can handle anything thrown at me.

Do you only train in Pinetown?

I now go to Doha from the end of May for two weeks too. They have everything under one roof with dieticians, MRI machines and amazing facilities. I try to train for ten swimming sessions and two or three gym sessions per week. I do a total of 27 hours in a week there.

How would you describe the general state of swimming in South Africa?

It is still ‘a white man’s sport’. That is not to be racist, as I want to encourage everyone to swim, but culturally we have grown up swimming. We have a lot of drownings in South Africa and water safety is a big issue we need to look into and improve it.

How can you and your Olympic profile improve this for swimming in South Africa?

People come together through sport. I want to be recognised internationally and for our swimming team to be recognised like the cricketers and rugby teams here. That will take swimming to a new level and people will say ‘Hey the swimming team is on at 9pm tonight.’

Chad Le Clos during the Abu Dhabi Swimming Festival at Emirates Palace Hotel on February 28, 2015 © Getty

If the kids all watch it will inspire a generation of youngsters to follow in my footsteps – that’s the goal.

What influence has your coach Graham Hill been on you? His reputation is as a tough task master.

Graham is never ever satisfied with my training, I can never quite meet his expectations, which is good. I think he still sees me as a 13-year-old boy, but I’m Olympic champion now and things are different. My dad and Graham have their ups and downs, but I try not to get caught in the middle of the fights. But we are a family and you can get caught in the middle.

How have you both coped with his prostate cancer problems?

The moment he told me and sat us down to tell us it was hard for me. It was overwhelming because you do not expect it to happen to your dad or anyone you know. It was hard for him to tell me and not interrupt my training as he wants me to achieve great things. He has his moments when he is not not himself and I know it’s the cancer speaking.

It must have been devastating coming after your mother’s problems too?

Mum went through the same thing in 2010 and it was just before my 18th birthday and the Commonwealth Games. They kept it from me for two and a half weeks as they did not want it to affect me and told me on April 20, 2010.

Geraldine Le Clos, mother of Chad Le Clos of South Africa poses with his gold medal after the Men's 200m Butterfly Final at Tollcross International Swimming Centre at the Glasgow 2014 Commonwealth Games on July 26, 2014 © Jeff J Mitchell/Getty

What is it like going to Rio knowing they are both suffering ill health?

I guess they help each other but I think my dad sometimes feels alone, even though he is not. He is very scared of dying. I know it’s not cool to say that, but I know he will do everything to get himself over the line. My mum Geraldine has breast cancer which has returned since her remission in 2010. She has recently undergone a double mastectomy and is now having chemo.

He is a proud father and has never changed.

My dad developed prostate cancer and has also undergone an operation in late June. I just wished it could have happened to someone else – even me. I’d rather mum and dad were healthy than win any gold medal.

How has it affected your preparations?

It has been the most difficult few months of my life; my family, the swimming and the pressure of the Olympic Games. But I have never trained as hard and it is as if their sicknesses has been pushing me through. From that point of view it maybe a blessing in disguise.

What has your dad’s influence been on your career?

No words can describe his input. I remember my first competition aged seven at Penzance Primary School and dad was there shouting ‘swim, swim. Come on boy, go boy.’ I didn’t even come in the top five, but he gave me my favourite chocolate after and said ‘attaboy, you did well son.’

Chad Le Clos and his father, Bert Le Clos attend the Laureus Welcome Party at the Rio Scenarium during the 2013 Laureus World Sports Awards on March 10, 2013 in Rio de Janeiro © Ian Walton/Getty

He has been the same from there all the way to the Olympics. He behaved the same when I made my first soccer team for Durban and Districts Provincial State side. It was not a huge achievement, but he was crying his eyes out. He is a proud father and has never changed.

What do you expect from Phelps in Rio?

He will be really fast as he would not have come out of retirement otherwise. I believe it will be great for our rivalry but unfortunately he has another thing coming.

I picture myself in the Olympic final – beating him.

Every single day I picture myself next to him in the pool and see him next to me with that jaw, that strike and I picture myself in the Olympic final – beating him.

Chad Le Clos competes during a swimming men's 100m Butterfly heat © Al Bello/Getty

Glory has brought you fame and sponsorship. What are the good and bad points?

I felt like Justin Bieber doing commercials for the Olympics and I’ve seen on Google a graph of Chad’s love life. I’ve been been enjoying it – who would not want to have beautiful girls looking out for you?

Follow Chad on Twitter @chadleclos