New UFC middleweight champion, Nigeria’s  Israel Adesanya was just 10 when his family uprooted him from Nigeria to an all-white school in New Zealand.

The only black kid in his class, he was relentlessly bullied until he learned to fight and stand up for himself.

Since then the lean 6ft 4in 30-year-old fighter has had a chip on his shoulder, bragging and smack talking to all who would listen.

On Sunday he backed up his talk by crushing Robert Whittaker in two rounds before a record crowd of 57,000 in Melbourne to become world champion.

‘I’m real petty you know that. I remember everything like an elephant. I was in the nosebleeds and now I made his nose bleed,’ he gloated in victory.

Adesanya’s journey from the nosebleeds to world champ started when his well-off parents decided to move out of Lagos to give their children a better education.

His father Femi, an accountant, and  mother, Taiwo, a nurse, were tossing up between the U.S. and New Zealand and ruled out America after the September 11 attacks.

‘I went to Rotorua Boys’ High School and there’s a lot of testosterone. It was ups and downs, smiles and frowns,’ he told Sporting News.

‘It was weird being the only black kid around. I had to defend myself a lot.

‘I’m cheeky, I’m annoying so I’d always get myself into trouble and eventually I had to learn how to defend myself. That’s when my search for fighting came through.’

Adesanya said he struggled to fit in and never felt accepted in his adopted country because of his race and being an African immigrant.

‘Literally there was a point through high school where I used to try and sound like [my classmates], I used try and be like them and talk like them,’ he said last year.

‘Just so I can fit in. I tried so many times to fit in but I could never ever fit in. I was always like, an outcast.

‘At the end of the day, look at my skin. I’m all black and ironically that’s the country’s national rugby team’s name.

‘I was never able to fit in properly and be accepted when I was a kid.’

Four fighters knocked back the chance to face him in his first UFC bout until Australian brawler Rob Wilkinson took him on

School was also the origin of Adesanya’s notorious swaggering self-confidence that made him such a loudmouth in and out of the ring.

He started giving himself motivation pep talks, and first to get through the day and then to push himself to become a champion fighter.

‘I think I was crying in the mirror one day after being picked on,’ he told the New Zealand Herald.

‘I was upset and I just kind of talked to myself and then eventually I just started doing it. I’ve been doing it for years now.

‘I don’t like eating my own words and I like rubbing it in people’s faces.’

In another interview he also attributed some of his his divisive attitude to his African upbringing.

‘I think it’s a trait of people from my place. We don’t shy from flaunting our abilities, even if we fall flat on our face, we still put it out there,’ he said.

‘It ain’t bragging if you can back it up, and I’ve been backing it up for years now, so I can say what I want and do what I want.’

Adesanya had trained briefly in taekwondo in Nigeria but his mother pulled him out of class when he broke his hand.

Almost a decade later he started to learn kickboxing after being inspired by the Muay Thai film Ong-Bak.

• MailOnline