Didier uprooted his entire life in Canberra to move to Melbourne and chase a UFC contract under the guidance of Daniel Kelly last year. Yet before long he sat alone in the gym, wondering if the sacrifice had been worth it.

Doctors said the mixed martial arts heavyweight would never fight again due to a blood clot in his right leg which should have forced him into retirement with a 7-1 record.

A last-ditch effort to keep his dream alive led him to a vascular surgeon in Melbourne named Doctor William Campbell. Unbeknownst to Didier, the man trying to save his career had represented the Wallabies alongside his father 30 years ago.

Today, the dream is alive, and Didier "would hate to be that first fighter" in his way.

Didier was sitting on the side of the mats inside Footscray's Resilience Training Centre with one thought running through his mind: "what am I doing?"

He had moved to a new city in September 2019, and within weeks a torn bicep ruled him out of a fight with Steve Warby. In time the bicep injury would heal, but the worst was yet to come.

Right on cue the coronavirus pandemic would hit to leave Didier out of work. Then he noticed his right leg was swollen. Everything he tried came to no avail.

Not for the first time, Didier had been diagnosed with a blood clot in his iliac vein. This time, he was told his career was over.

"It was pretty much my worst nightmare, I was in lockdown and I had this blood clot," Didier said amid a 13 and a half minute response to a question about his move to Melbourne.

"The first hospital I went to in Melbourne, they gave me the same outlook I got in Canberra a few years ago. They said 'you've got an unusual vein structure, this is going to continue to happen, you need to be on blood thinning medication for the rest of your life'.

"For me to hear that again, it was heartbreaking. Obviously lockdown was occurring as well. I was sitting on the side of the mat, I got told my career was over and I was questioning everything.

"I thought 'what am I doing?' I'm down here in a new city with a massive blood clot, it looks like my career is over. It looks like I'm going to be on blood thinning medication forever.

"I wasn't happy with that answer. I went to my GP down there, and got a referral to a vascular surgeon. That was when I met Bill Campbell."

Dr William Campbell stands at 202 centimetres tall. He's the kind of man who walks into a room and "has a presence about him" - yet beyond that, Didier knew nothing of the man he was hoping could save his career.

Not until their second consultation, at least.

"When I looked around the room, there were all these old rugby photos and they look very similar to the same photos I grew up with in my study at my dad's house," Didier said.

"When I saw that I asked him, 'are you a rugby man?' It was the most beautiful answer I have ever heard in my life, he goes 'yeah, I played for the Wallabies from 1984-90'. My father played for the Wallabies in 1990, so I looked at him and said 'did you play with my dad?' He said 'yes, yes I did play with your dad'."

Campbell wasn't just a Wallaby - "this man was a legend". The former international lock played 26 Tests and was vice-captain in 15 of them. He was a Queensland captain who balanced rugby with a flourishing career in medicine during an era when camaraderie reigned over capital.

"This man is the most incredible man I've ever met," Didier said.

"I realised then and there, somehow, some way, the universe has got me to this random vascular surgeon in Melbourne, and I've somehow found the right guy for this job.

"I'm getting tears in my eyes just saying it now, I got my tears in my eyes then, I get tears in my eyes every time I think about it."

Campbell cut through Didier's neck, his legs, and fed a wire through his body. He created a passageway through Didier's left side which had been shut off for years.

After seven hours under the knife Didier woke up to the sickening realisation that the problem wasn't fixed. The good news was his left side had better circulation than ever.

"The issue was it was my right side that was giving me complications. He said 'I still think I can fix the right side, I want another surgery'," Didier said.

"For the next eight weeks, I was recovering from surgery, I was on the strictest lockdown in the world, I had no part-time job due to COVID, and it was the toughest time mentally for me.

"I've had some ups and downs in my career. I've won Australian titles in three different sports, I've competed all over the world, I've competed in front of my friends and family, I've competed at the Commonwealth Games and I've missed the Olympics.

"This was honestly the hardest time of my entire life."

Didier shudders to think how bad things could have been if not for the support of a select few friends, his coach, and his girlfriend Alex.

Living together in a one-bedroom apartment in Melbourne in the midst of a pandemic was extremely challenging - so much so that Didier says "we've put 10 years on our relationship, and we're rock solid".

"It was horrible. I still didn't know if I was being fixed, I couldn't do anything, I couldn't come home to see my family," Didier said.

"We had the next surgery, I woke up, Bill was there, and he said it was fixed. He said I've got better blood passageway in both my legs than I have ever had in my life.

"Not only did he fix my blood clot issues that two other hospitals said would never be fixed, he said 'you'll be better than you were before the blood clot'.

"I'm so excited to think everything I've done in my life and my career was done with shoddy circulation and legs that gassed out quicker than they should have. It's one thing to say I'm new and improved, but I've got medical proof, I've actually improved."

So now it's time. Didier is on the verge of returning to action more than a year after submitting Jeff King in a first-round finish that lifted the roof off the Hellenic Club of Canberra.

Didier will be on blood thinning medication to iron out any lasting complications with his leg until February, at which point training will ramp up in Footscray.

"After that I have one last tilt in me, one last big push," Didier said.

Didier has his eye on a fight in June or July, and says fighting in Canberra is always his first preference should the opportunity arise.

After all, his pre-fight declaration leading into his bout with King last year was that "three things in life are certain: water is wet, fire is hot, and Duke Didier doesn't lose fights in Canberra".

Yet if a chance to fight in his adopted hometown pops up, then fight fans in Melbourne may soon be privy to a man in a black and green gown making his way to the cage with Bon Jovi's You Give Love A Bad Name blaring through the venue's speakers.

"Any ranked heavyweight in Australia is on my list. I've already beaten the No. 1 in Australia, Sam Kei, I've already beaten a few on that list. I'm undefeated at heavyweight, I'm 6-0 at heavyweight," Didier said.

"A lot of those heavyweights rely on their punching power and don't do the hard yards in their grappling, I can't wait to expose a few of these blokes.

"After everything I've been through, I feel like whilst it was horrible and whilst it was challenging, it's going to make everything moving forward all the more sweeter. It's going to make me appreciate every single little thing. I do now."

Being able to go for a jog around the lake is a luxury Didier didn't have for so long. But now Melbourne has, touch wood, fought its toughest battle with the coronavirus and come out the other side.

Though we know how quickly that can change and new restrictions can be imposed.

"I consider it a second home now, I love Melbourne, I'm not going anywhere until I finish what I started," Didier said.

"I've got some great mates down there, most of my mates down there are fighters. We've all got the same goal, we're all on the same path, it's the right environment for me right now.

"I'll never turn my back on Canberra, I'll end up dying here. As soon as my sporting career is over I'll be back here. I'm now in the best place I've been for about a year.

"I just can't wait to get in there and show all the sacrifices I have made. I'd hate to be that first fighter."

So who might that first fighter be? First things first, Didier wants to clean out his own backyard - but he will leap at an opportunity to take a short notice fight in the UFC if it arises.

The national judo champion is moving to the heavyweight division after UFC light heavyweight Jimmy Crute told Kelly just how much stronger Didier felt during training when he added some size.

Now Didier runs his eye over the lower level of the UFC heavyweight division and all he can see are "holes and opportunities".

The former Commonwealth Games representative says his grappling is at a level that can go with anyone in the world. He has been honing his takedowns and groundwork for more than 20 years.

All he needs is a chance - because Didier is adamant he can match it with anyone, "especially in this country and definitely at the lower level of the UFC".

"Eventually I'll work my way up the UFC ladder. If there's a short notice fight in the UFC, I'm 6-0 at heavyweight and 7-1 overall, I'm happy to prove it," Didier said.

"Any time after June, I'm ready to go. I guarantee I'll have the best preparation and people around me. Bring it on."