Conor McGregor is preparing to take on the reigning UFC lightweight champion Khabib Nurmagomedov at UFC 229 in Las Vegas this weekend - but who is Nurmagomedov, and how has he risen to the top of the sport?
Nurmagomedov, the only Russian and first Muslim to win a UFC title, is a ferocious competitor boasting the longest undefeated run in MMA history - 26 wins from 26 fights across a decade-long career.
Born in 1988 in Dagestan in the north Caucuses - now in Russia but at the time still part of the USSR - Nurmagomedov is of Avar origin.
His father, Abdulmanap, was a much-decorated army veteran and taught him wrestling - a sport that is massive in that region of Russia - from the age of eight.
After Abdulmanap converted the downstairs floor of their home in the town of Kirovaul into a gym, Khabib began getting seriously interested in mixed martial arts.
It was also the beginning of Abdulmanap's long career developing top wrestlers and martial arts practitioners.
But it was his son who would go on to have the most successful - and high-profile - career.
Nurmagomedov's win over Pat Healy elevated him to star status in UFC
Khabib learned from his father not only wrestling but judo and then sambo, a mixed martial art originally developed by the Soviet Red Army in the 1920s and designed to be a combination of the most effective techniques from across a range of disciplines.
Sambo is an acronym for SAMozashchita Bez Oruzhiya - which translates in English as "self-defence without weapons".
Nurmagomedov's first MMA bout was in September 2008 and he quickly found his feet - winning won four fights in just one month.
By January 2012 he was competing in UFC and claimed his first win with a third-round submission against Kamal Shalorus.
And in 2013 he really grabbed the attention of UFC devotees with two highly impressive performances - first, in May, defeating Abel Trujillo while setting a new UFC record for the most takedowns in a single fight - 21 out of an attempted 27 - and then beating American Pat Healy on a unanimous points decision in September.
The manner of his win - marked by a series of stylish slams - had UFC president Dana White purring.
"The kid is exciting. We're probably going to do big things with this kid," he said.
However, while Nurmagomedov continued to fight sporadically, a series of injuries and cancelled fights in the years that followed blunted his momentum, and it was not until April 2018 that he fought for the UFC lightweight championship.
The bout was meant to be against Tony Ferguson - the fourth time a meeting between the two had been scheduled - but yet again there was a problem - this time a knee injury to Ferguson, who was replaced by Max Holloway.
Holloway was himself then declared unfit - he had been trying to cut his weight to a degree that was deemed unsafe - and replaced by Al Iaquinta, who proved to be no match for a dominant Nurmagomedov.
And it was that result that set the Russian up for McGregor and Las Vegas.
Nurmagomedov has promised to win over fans, despite the enormous popularity of McGregor - a former two-weight champion.
"I know you're going to love me," he has declared.
If he wins, he'll certainly be better known. But better loved? That might take some doing.