Every now and then during his blockbuster murder trial, Oscar Pistorius could be seen deep in conversation with a pony-tailed , 43-year-old courtroom sketch artist called Jaco van Vuuren. Was the disgraced athlete discussing his defence strategy, his deepest fears, his possible fate?

“Me and him being bachelors, I tried to talk about women, if there’s any hot media girls, that type of thing,” Van Vuuren recalls, laughing. “Also his knowledge about athletics was still brilliant. He knew about times run yesterday in a competition in America and everything of that sort. So we spoke mainly about athletics.”

Sitting at a fish restaurant in one of Pretoria’s roadside strip malls, he can now draw breath and reflect on the televised courtroom epic that dominated 2014 on his sketch pad and on screens around the world.

He played a double role, as an athletics coach who has known Pistorius since he was 16 and as the only court artist charged with capturing his tearful, visceral dismantling. The Paralympian, dubbed the “Blade Runner” because of his prosthetic limbs, was found guilty of culpable homicide for shooting dead his girlfriend, Reeva Steenkamp, and jailed for five years.

Van Vuuren, who hopes to sketch him in prison, relays a story he heard from a warden: “The biggest problem now for Oscar is the top brass at correctional services coming into his cell day and night and taking selfies with him. There’s no control and the lower ranks can’t chase them out, so Oscar is annoyed.”

Van Vuuren is a former international pole vaulter with a respectable personal best of 5.20 metres. Since 1992 he has been coaching pole vaulters at the University of Pretoria, where his path first crossed with Pistorius. He has been a court artist for four years, covering some of South Africa’s biggest trials, including former police commissioner Jackie Selebi’s corruption conviction.

“I ended up as a sketch artist in court because of an absolute obsession,” said the art teacher’s son. “There was no money. I just had to do it. There was no other way.”

Jaco van Vuuren on Pistorius: ‘Whoever he is, whatever he did, he is probably a bigger survivor than all of us together, looking at what he went through in his life.’

The essentials of a face typically take him two or three minutes, and the full sketch anything from 20 to 45. “It’s always an eerie feeling before the judge does a life sentence.” There have been divorce cases, too: “The body language, they just hate each other, there’s so much emotion going there.”

In early February 2013, Van Vuuren had a drink with Pistorius to discuss helping the sprinter’s charity projects for amputees in Africa. On the morning of Valentine’s Day, he was woken by a phone call. “I was in bed, very early, at about a quarter past six and a reporter from [the newspaper] Beeld called me and said, ‘Did you hear what your friend did?’ Being sarcastic I said, what friend where? He said, ‘No, Oscar’s shot his girlfriend’.

“On the track that day it was obviously a feeling of disbelief. It was indescribable. He trains there every day and he shot his girlfriend. It’s somebody that we are obviously very proud of because it’s Oscar Pistorius, he’s the biggest name next to Nelson Mandela in South Africa. That’s on the level that he was seen, and all of a sudden this.”

The nation remains numb with shock, Van Vuuren believes. “I still think that South Africans can’t cope that well with the idea. It will still take time, even longer than this, because you can’t admire and support a guy in the Olympics the one day, and the next day he’s in an orange jumpsuit. I don’t think people are there yet. I actually heard of a psychologist that wanted to open centres for therapy for people – I think that’s a little bit too far, but that’s how bad it was.”

From the start, Pistorius maintained that he had mistaken Steenkamp for an intruder when he armed himself, walked down a darkened corridor and fired four lethally expanding bullets through a locked toilet door. The 29-year-old model and law graduate had no means of escape and died almost instantly.

Van Vuuren believes the Olympic runner’s version of events, but adds a new, intriguing twist. “The one thing’s that not mentioned in court, and we still don’t know why it’s not been brought up: he was as nervous as hell a week before that happened. He was on the track and I heard this from another Olympian who trained with him. He was as nervous as hell as if something was bound to happen.”

Over eight months, the “mega-trial” gripped the public like the murder cases of Victorian England, only now there were the modern trappings of TV cameras, Twitter and book deals.

Proceedings veered from opera to soap opera, with a cast that included a black female judge, expert witnesses of sometimes questionable competence, and a social milieu of Pistorius’s neighbours, pals and former girlfriend.

The celebrity in the dock repeatedly broke down, wailing and weeping like a child. Van Vuuren, in court to draw it all for broadcasters including CNN, found the spectacle difficult to watch. “You’re first of all a track friend but you’re also a courtroom artist and there’s always the discretion you have to use. It was a draining process from start to finish.

“Knowing him very well it was hard emotions and I must honestly admit, from time to time you want to bloody headbutt him, and then a second on you want to hug him and say you got it wrong, let’s work through this.

“A lot of times you had to cut off your emotions and say you’re here for a reason.”

On one occasion he had to pass the sick bag. “It was tough when they went through the visuals and Oscar started puking,” he recalled. “I was sitting next to him, about two metres away, and then he started puking and what I did was clean out my bag because I knew he was dry heaving. I threw the plastic bag to him; all my Koki pens were thrown out. It was the only bag I could use because I couldn’t get the attention of the court orderlies. I threw the plastic bag over the barrier into the dock, so he used that.”

Asked if he tried to sketch Pistorius in the act of vomiting, Van Vuuren replied: “Never. I said this is where I draw the line. Use your discretion and integrity.”

Prosecutor Gerrie Nel, dubbed the pitbull, mauled Pistorius and other witnesses during cross-examination and, like a dog with a bone, will appeal against the culpable homicide conviction at the supreme court next year. But Van Vuuren says there is another side to him. “I bumped accidentally into Gerrie Nel a couple of days ago in Exclusive Books [a retail chain]. He’s quite upbeat about the case, although he actually feels sorry for Oscar. Even Gerrie Nel said it can’t be easy for the guy in jail. So he’s got a heart, but this is the law.”

Van Vuuren said Pistorius’s aunt called him recently because the 28-year-old wants to start sketching in his prison cell and is seeking tips.

“He takes it day by day. We have to know, whoever he is, whatever he did, he is probably a bigger survivor than all of us together, looking at what he went through in his life.

“I’ll tell you one thing, Oscar will give anything in his power to change that day, go back and not do it. One day in jail is 10 years too many. South African jail is a hellhole of note. I once went to visit a prison and you don’t want to go there. Lying around there from where he was, my heart goes out to him.”

Van Vuuren, who recently turned 44, may never draw a trial on such a scale again. But he has discovered his vocation. He said: “Court is the best place in the whole world for me to be. I see myself as very fortunate to be on that spot where it’s always a make or break for this person. It may be a sombre mood, but the intense emotion in that stillness – I feed from that emotion.”