He is on his way to becoming one of the most feared fighters in the world, but tough-talking Dubliner Conor McGregor didn't always have the trademark swagger he carries into the ring today.
n fact, it was the beatings he suffered as a child growing up on the streets of his home city that motivated him to succeed at the highest level on the mixed martial arts arena.
The Dubliner is now a global phenomenon and cemented his growing reputation with a first round defeat this morning of world number five Dustin Poirier in the latest chapter of his glittering UFC career.
But it was the brawls in which he came off second best as a youngster that inspired him to learn how to defend himself properly.
McGregor told the Sunday Independent: "When you grow up, as a young boy, fights happen.
"Every kid gets involved in little fights and scuffles but when it happened to me it always stuck in my head and I would ask myself, 'What should I have done there? What way should I have moved?' I could handle myself a bit when I was a kid but I wanted to be able to defend myself without a doubt in my mind."
McGregor has taken this unshakable belief into the ring, winning all of his four of UFC fights to date.
He said the opportunity to fight in the arena where heavyweight boxing legends Mike Tyson and Evander Holyfield did battle is a dream come true.
"It is the fighting capital of the world," said McGregor.
"I grew up watching fights there and now the fighting Irish are heading to the fighting capital of the world. It is a beautiful thing."
McGregor's coach John Kavanagh spoke recently of his excitement to see his fighter go to battle in one of the world's great fighting arenas.
"I was in Vegas with Conor last year organising a work visa and I walked up to the hotel and I stopped myself from going in because I didn't want to do it unless I am going in with one of my fighters," he told the Sunday Independent.
More than 600,000 people tuned in to McGregor's last fight on Irish station 3e, with thousands more viewers tuning in online and on BT Sport.
However, the sport - and its brutal, no-holds-barred style - has attracted its fair share of critics. During McGregor's first round win over Diego Brandao last month, RTE's Tony O'Donoghue tweeted: "Sorry but that's disgusting. #NotSport."
But McGregor, typically, is not bothered.
"I don't give a s**t really. This is a billion-dollar business here and I don't care what people are saying. I am going over to Vegas to fight in one of the biggest pay-per-view events of the year. People can moan about that but I have made it. There are always critics but one thing that there are not is accomplished critics so I don't listen to it. I just keep on doing my thing, securing my future, securing my family's future and showing another path that kids can take," he added.