Conor McGregor during last month's explosive media conference in Los Angeles. Photo / photosport.nz
By Gareth A Davies for The Telegraph
According to his mother, Margaret, Conor McGregor "was born with his fists clenched".
That fighting spirit - which was kindled on July 14, 1988, when he was born in Dublin's National Maternity Hospital - has fuelled his rise from a trainee plumber on the dole to earning over £60 million in a boxing bout against Floyd Mayweather in Las Vegas on Sunday (New Zealand time).
The man himself has recalled a neighbourhood "synonymous with gang culture, there were grenades getting put through people's letterboxes".
Tony McGregor, Conor's father, paints a different picture of life in the semi-detached house in Clonmacnoise Road.
"We had great years living in Crumlin," he told the UK Daily Telegraph.
"Conor was born and spent his formative years there. There are some great people in Crumlin. You just have to be streetwise.
"Drugs have ravished most areas and that happened to Crumlin. That's still going on to this day. Overall, though, Crumlin is a nice, respectful, working class area."
There was nothing which marked young Conor out as a future global fight star.
"It was a very normal upbringing. He didn't really want anything. He had all the latest toys, the latest PlayStation and the latest bike. There was nothing outstanding about his upbringing at all. That's what makes it all the more remarkable for us."
'Boxing was always close to our family'
McGregor was 13 when Tony moved the family to a bigger house in the leafier surrounds of Lucan, west of the city, keen to provide a stable home for his young family.
The move, though, meant a new area and a new school.
Though boxing was his first combat pursuit, it was not his first sport.
As a child, he had followed Manchester United and, aged seven, with a mop of blond hair, was already kitted out in red and white.
McGregor played football for Lourdes Celtic and other local clubs, but in his early teens he opened the door to Crumlin Boxing Club.
He did not look back.
"I always knew he had capable skills as a boxer," explained his father.
"My father was a boxer as well. He was a championship boxer, but only at amateur level."
McGregor would return again and again for three years to Crumlin Boxing Club, under Phil Sutcliffe, a two-time Olympian for Ireland.
"He was a good kid, he did as he was told," recalled Sutcliffe.
"He trained harder than a lot of the other kids. He was extra careful of not getting whacked. He was a very cute orthodox southpaw, and a very good counter-puncher.
"He was just getting good when he went to that mixed martial arts stuff. I didn't like it. I still don't really like it.
"I don't like anybody being hit on the ground and no one coming in and them constantly being hit.
"Most of Conor's fights [in the UFC] are stopped with punches. He got his boxing ability from here. He punches the way he was taught - properly. That's probably why he's knocking so many guys out."
McGregor matches his brash deeds with words and the trash talk troubles Sutcliffe.
"People look up to him. I think he's only using the language because it draws more attention. That's not the Conor we knew. The Conor we knew tried very hard and was very dedicated.
"He knows what he wants. He draws attention. He has that quality. He's like Muhammad Ali in a way. A lot of people want to see Conor get a few clatters.
"A lot of people want to see him win."
'He knew he would make it'
But outside boxing, a new sport was emerging.
For McGregor, MMA was fast, furious, different - and utterly captivating.
"I think he knew where he was going and he was getting better results with the UFC," said Sutcliffe.
"He was getting better results there than he was with boxing. It was happening faster there and he could see something that was good for him. He's proven it."
McGregor's timing was in again when he joined a training group which included former UFC fighter Tom Egan, and martial arts coach John Kavanagh.
They formed the perfect trinity, and McGregor had a new calling.
"He just had a love of mixed martial arts. It took over his teenage life," said his father.
"Conor had been popping in and out of different sports until he found something that suited him.
"That must have been tough on a little 14-year-old kid.
"It's kudos to Conor for being able to overcome that as a young boy. He was put in a different area, all his mates were left behind and he had to find a new school.
"He met Tom Egan in that school and Tom's love of mixed martial arts rubbed off on him. Once he found his niche, he knew then he was going to make it."
'He had the intelligence to become a lawyer'
McGregor's wing man, Egan, recalls them being allies.
"I believe it was fourth year, fifth year of high school or something like that; I remember seeing Conor," Egan recalled.
That led the pair into the path of Kavanagh and his Straight Blast Gym, although there were concerns when McGregor left school at 16.
"He never had an interest in taking education further," explained his father.
"One of his teachers at secondary school said he had the intelligence to become a lawyer. That he had the academic ability to uncover and analyse detail. But he just didn't have the interest.
"He knew what he wanted to do. He was ahead of the curve. I didn't see a career in it at all. But I've thankfully been proved wrong."
The SBG training facility in Dublin is now world-renowned. Paddy Hoolahan, a former UFC fighter and training partner at SBG, said: "Conor's like the commanding chief at the moment and John is the general.
"When Conor has won belts in the UFC, all the guys rolling around here get the chemicals that come from watching another Irishman get to the highest level and win a world title. That's enough motivation on both sides."
Hoolahan says McGregor and Kavanagh make the perfect duo.
"Even though Conor truly believes in his ability, John is a sceptic. He has the mind and the reason. He will put a plan in order and guide things. It's a perfect combination."
There is also no change in him, either.
"Conor's always been the same to me. He has suits and stuff but he deserves every single one of them. He sets trends. Conor is the biggest sporting athlete in Ireland.
"He's probably in the top five or top 10 in the world. He said it, he believed in it, he stuck it out. He deserves it."
An Irish passion for fighting
As UFC president Dana White described this week, McGregor is "about to earn life-changing money", but it was tougher when he started out.
"By the time he'd won two titles in [European MMA organisation] Cage Warriors, we were 100 per cent behind him," said Tony McGregor.
"I was still a bit concerned, though. He was getting probably €2,000 pay cheques, which wasn't bad for a kid his age."
Aged 20, McGregor had a life-changing moment when he met his heroes - UFC star Chuck Liddell and promoter White - during a UFC visit to Dublin for an event, in 2010.
McGregor was now fired up, ready to excel. He was even calling on the family's famed warrior lineage.
"The name McGregor is steeped into Celtic warrior folklore," McGregor once explained.
"The Irish passion for fighting comes from a long history of battle. I know my ancestors and my bloodline is on the battlefield; they were doing it riding a horse with a sword, swinging an axe.
"Now I'm doing it in the Octagon."
With victory after victory in the UFC, predicting how and when he would win, McGregor's army of supporters grew rapidly.
'He knows what he wants'
"He's made that much of a crossover," said Kieran McDaid, editor of The Irish Sun, who equates McGregor's stardom in Ireland to that of rugby union legend Brian O'Driscoll.
"Everyone talks about his sporting prowess, his charisma, his personality, but he's also a great story teller," he said.
"He's got the rags to riches story down perfectly. He made his UFC debut and he was on the dole.
"The week after that he appeared on Ireland's biggest chat show The Late Late Show."
With an eye for cool, and a sharp suit, three years ago, McGregor was voted the most stylish man in Ireland, courtesy of his Dublin tailor Louis Copeland, who has dressed everyone from Bill Clinton to Pierce Brosnan.
"When he walked into the store you could feel the energy," Copeland said.
"He lights up the place. Everybody looks at him. We used to dress Alex 'Hurricane' Higgins and he was the same. They just have this star quality.
"Conor's a very stylish man. He knows what he wants. He's a great fighter but he also has a great knowledge of clothes and how they should fit. I didn't have to educate him too much."
'The word proud doesn't do it justice'
Without the support of the McGregor family, the fighter may never have risen to such heights.
They remain a close family.
Tony and Margaret, his parents and his elder sisters, Aiofe, a self-employed make-up artist, and Erin, travel to all his fights.
"You will get some haters, but the majority love him for who he is. He's honest. He's very generous," said Margaret.
"I think he gives a lot of people hope. He is everything you see, but he's still honest and says it how it is. I'm extremely proud of him.
"He is a mummy's boy. He'd probably kill me for saying that but he is."
Erin goes even further.
"As an older sister to watch your younger brother succeed in his dreams, the word proud doesn't do it justice.
"I love the fact he stays true to himself. Even though he's my little brother I still hugely look up to him and admire him for that."
UFC President White now counts McGregor as one of the greatest stars of the fighting organisation's history, recently describing him as 'The Unicorn' with the fighter having held both featherweight and lightweight titles simultaneously, while consistently drawing a pay-per-view audience of over a million.
"Conor is not just good at the fighting and the talking, he's good at every type of warfare there is in the business," explained White.
"The mental warfare, the physical warfare, the whole thing. That's why I call him The Unicorn.
"There's no one like him," he added.
"I really believe he's the best at selling a fight since Muhammad Ali.
"And you can't rule out McGregor in this fight. I stopped doubting him a long time ago."
Williams has a lot on his mind as he gears up for the biggest bout of his career.