Kamaru Usman has beaten some of the biggest names in mixed martial arts - and all while they were in their prime.
The formidable UFC star holds wins against Jorge Masvidal, Rafael Dos Anjos and Colby Covington and beat Tyron Woodley for the welterweight belt in 2019.
Now he faces Gilbert Burns, a man who has won his last six UFC clashes and claimed a ‘Performance of the Night’ victory over Woodley last time out in May.
Usman is yet to meet his equal in the octagon so far and will be looking to make another huge statement at UFC 258 against Burns this weekend.
What is Usman's record?
Currently it's 17 wins and one loss. Seven of those successes have come via knockout and one via submission. Currently, he is on a 16-fight win streak.
His last loss came way back in 2013.
Why is he called The Nigerian Nightmare?
Usman was born in Nigeria, but moved to the US at the age of eight when his family migrated.
He began wrestling at high school in Texas and was one of the country's best prospects throughout college.
"While I was there I started to get different offers and different chances to help other professional fighters," he told the BBC in 2019.
"It was kind of time to make a switch and not just be a wrestler any more, but to be a fighter and to go and make a living for not just myself but my family as well."
"This nickname symbolises the greatest athletes all over the world in different sports that are Nigerian born," he said.
"It was the rightful nickname. I was the first one in the sport at this calibre, at this level, so when it was time to choose a nickname it was the only fitting one."
His nickname is shared with Nigeria-born former NFL star Christian Okoye.
When did he make his UFC debut?
An NCAA Div. II wrestling champion, Usman begun fighting professionally in 2012 before winning season 21 of the promotion's reality show, The Ultimate Fighter in 2015.
He has since enjoyed an 12-fight win streak and is tied with Georges Saint-Pierre for the longest UFC welterweight win streak.
How long has he been welterweight champion?
The champion wrestler dominated Woodley at UFC 235 in 2019 to become the promotion's first African-born champion.
Joe Rogan called it 'one of the most spectacular performances' he has ever seen in his career as a commentator.
How hard does he hit?
He fought and beat Covington in December at UFC 245 in his first title defence and broke his opponent's jaw in the process.
A dominant all-rounder, he is yet to fight someone capable of mixing it up with him in the cage.
"I'm the best in the world," he boasted after his most recent win.