“I’d been in an absolute battle, and the adrenaline was still pumping,” Frazer Clarke says as he remembers the harrowing aftermath of his fight against Fabio Wardley in March. Their British and Commonwealth heavyweight title bout was a ferocious and gripping contest that ended in a draw and the rematch will take place in Riyadh on Saturday night. Clarke had been knocked down heavily in the fifth round but the canvas was splattered mostly with the blood of Wardley, who also went through hell.

Before he considers the prospect of returning to a dark place in the ring with Wardley, Clarke talks in riveting detail about the consequences of that first bout at London’s 0₂ Arena. “My girlfriend, Danni, had gone to bed because she was emotionally drained. She was in bits. So I went up to her and this is what people don’t see. I’m in our room and I’m really hot, really overheating. I’m getting as much water down as I can but my missus says: ‘You need to get some sleep.’ I say: ‘I’m scared.’ She asks why and I say: ‘I don’t want to close my eyes because I don’t know if I’ll be able to open them again.’”

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Clarke and I are sitting in a different hotel room in Westminster. It’s bare, anonymous and hushed while the 33-year-old boxer talks in an unbroken monologue. “It might sound like an exaggeration but my ears were ringing, my heart was racing, I was still sweating. I’m sitting in darkness and the room felt like a sauna. I could feel the blood trickling out of my ear.

“Danni was worried. She was like: ‘Should we call someone?’ We probably should have done, but I said: ‘No, let me just drink some water and I’ll take some time before I lie down.’ I did that and, eventually, fell asleep. Thankfully, I woke up in the morning. But in those moments I felt bad and afraid.”

How was he on the morning after the fight? “Sore all over,” he says ruefully. “It was even harder knowing I had to go down to breakfast to see my family and everyone. I had loads of praise from everyone who saw me but it still didn’t take away that heartache.

“I wanted to have breakfast with the British title over my lap – and it wasn’t there. People don’t understand my life and the sacrifices I make, the time I can’t spend with my loved ones, my kids who I missed taking their first steps or saying their first words because I was away at a training camp. People never understand how hard it is to be a boxer.”

I show Clarke a photograph of the canvas after his fight with Wardley. It looks like a Jackson Pollock painting where blood rather than paint has been sprayed and splashed across the canvas. “I’ve seen that photo,” he says, “and it definitely tells a story and shows the reality of our sport.

“I love boxing but it’s dangerous and I have a beautiful family who come first. That photograph is a little reminder that you don’t want it to be your blood. But I’m human and I wouldn’t want to do any lasting damage to anyone.”

Wardley admitted that such fights can take years off a boxer’s career. “In some cases, definitely,” Clarke agrees. “You want an exciting fight but you don’t ever want one like that.”

Clarke then grins helplessly. “But we’re fighters and so, in a strange way, I enjoyed it. Then when you look back you think: ‘Bloody hell!’ A lot of people ask: ‘How do you do it?’ The honest answer is I don’t know.”

When the draw was announced, Clarke looked more disappointed than Wardley. “I knew it was close but a draw was devastating. Still, Fabio and I had a few words full of respect in the changing room. I thanked him because he brought the best out of me.

“It was a really emotional night but there was a beautiful moment when I walked into the bar at the Intercontinental, at the O₂, to a standing ovation from 300 people. Everyone wanted to buy me a drink. People were singing my name. Fabio walks in two minutes later to silence. That spoke volumes.”

Does a part of him dread returning to such dangerous territory in the ring? “I don’t mind going back there. I just don’t want my kids to see it. I don’t want my mum or my nan to see it. It’s hard to keep them from watching but I don’t want the women in my life to see me suffer.”

When the two fighters were reunited for a press conference in London last month, Clarke said he was looking forward to “smashing him in the face”. It seems very different now when hearing him discuss his interaction with Wardley. “This is a professional rivalry,” Clarke says. “It’s not a rivalry where we’re going to insult each other’s families or each other’s looks.

“This is just a case that “I want to be better than you in our sport.” That’s the kind of boxing rivalry I love. I think about him, and what I’m going to do, every now and then. Like any other boxer, if I walk past the mirror or a window, I throw a few punches at my reflection, as if it’s him, because I’m programmed to do it.

“We’re not normal people. We punch holes in each other to try and get the best out of each other, to try and improve each other. But, when you fight, you’re trying to destroy the person in front of you in that moment. This is my job and I take it very seriously.

“When I was a young amateur I’d think boxing was about life or death. But now I’ve got kids – a boy of three and girl of seven – I don’t want it to be life or death. If I win, amazing; if I lose I’ve given it my best but I hope I’m healthy.”

Clarke has skirted death outside the ring. In December 2016, while celebrating the birth of his daughter in his home town of Burton, he was stabbed three times. “I went out, wetting the baby’s head, and that was a bad decision. I had a few drinks, like everyone else did, as it was near Christmas. I got into an altercation which I thought was a normal bit of fisticuffs. I ended up being stabbed once in the neck and twice in the leg.

“In the hospital my mum and dad, all my friends, were holding me down because I was intoxicated. I was angry, but I needed a blood transfusion so had to behave. I’ve recently seen one of the nurses from that night. She said: ‘You don’t remember me but I was trying to help you when you were stabbed.’ It all came back to me, her face above me in her scrubs. So there have been some crazy moments but that was a great life lesson and I’m here to tell my story.”

Three months later, in March 2017, Clarke attended a boxing press conference at the House of Commons. Soon after leaving he witnessed the murder of PC Keith Palmer during the Westminster Bridge terror attack. “I walked outside to see an individual come round a corner with two Rambo-style knives and he was stabbing a police officer, Keith Palmer. Stabbing him to death 15 metres away from me. I could see it as clear as day. The police officer got free and ran towards us. He fell towards me and one of my coaches, Tony Davis, tried to resuscitate him. But, tragically, it was too late.

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“Then we got locked in the building while the police dealt with the attack on the bridge. I rang my mum and told her I’d been involved in an incident and she’d better put the TV on. She’s looking at the news and going: ‘Oh my God.’ The next thing the phone signal disappeared and it was a long eight hours of torture before we were allowed out.”

Clarke is about to return to the dark and unsettling business of boxing. “It’s crazy too,” he concedes. “Make no mistake that what I do is great. It’s entertaining. But it’s very dangerous. I put my life on the line to try and achieve my goal. It’s not a normal job, or a normal sport. In order for me to feel satisfied, I have to risk my life.”

Does his girlfriend want him to get out of boxing, especially after that last savage fight against Wardley? “No, not yet. She knows, while I am unfulfilled, it would be the worst thing for me to stop boxing. I set myself goals and, until I’ve given everything to try to achieve them, I won’t be stopping. So, if I have to, I’ll go back to the darkest places again.”