Khabib Nurmagomedov took the remarkable step to call out Floyd Mayweather just days after defeating Conor McGregor at UFC 229.
During an Instagram video with Mayweather Promotions CEO Leonard Ellerbe, boldly saying into the camera: "Hey, let’s go, Floyd. We have to fight now.
“50-0 vs. 27-0. Two guys never lose. Let’s go. Why not? Because in the jungle only one king. Only one king. Of course, I am the king because he cannot drop McGregor, but I drop him easily.”
Nurmagomedov would be following in the footsteps of McGregor, who made the move from MMA to boxing in a mega-money fight with Mayweather back in August 2017.
That ended in a convincing victory for the boxer with Mayweather - renowned as one of the greatest of all-time - securing a technical knockout victory in the tenth round.
Possible Mayweather vs Khabib fight
And it seems the American is more than happy to take on another UFC champion, confirming in an interview with TMZ: "Oh, we fighting!"
That's all well and good, but there are a number of obstacles in the way of a Nurmagomedov vs Mayweather bout and location is at the heart of the problems.
Mayweather has noted in previous social media posts that the fight would need to happen in Las Vegas, a location Nurmagomedov could be banned from after the UFC 229 fracas.
Khabib's Instagram post on Maweather
However, after days of quiet on the situation, Nurmagomedov has posted a serious update across his social media that could change everything.
Pictured with General Secretary of the Russian Boxing Federation Umar Kremlev, the 30-year-old has revealed his team is working on the fight and it could happen at Moscow's Luzhniki Stadium.
He notes that there would be no visa concerns in the Russian capital and a world-record broadcast sale has also been touted.
The translation offered by Instagram reads: "Today was a meeting with the Secretary-General of the Boxing Federation of Russia @umar-kremlev discussed the fight with Mayweather.
"We want the fight to be held in Moscow at the legendary Luzhniki Stadium.
"We are sure that we will collect 100 thousand viewers and also set the world record for the sale of paid broadcasts. Ah, most important, in the corner will be my father, to Moscow visa is not needed.
"And so the question to my fans: do you believe in me? Or do you think he's going to knock me out of boxing?"
The ball is in your court, Floyd.
Las Vegas or Moscow?
The fact Nurmagomedov has met with such a powerful figure in world boxing is certainly major and when it comes to Mayweather, money talks at the end of the day.
Like it or not, though, Mayweather has proven incredibly stubborn about fighting in Nevada in the past and it remains unlikely that he'd make the trip to Moscow.
Across his legendary boxing career, the 41-year-old never fought outside of the United States and his final 15 contests all took place in Nevada.
So, it would take some serious money for Mayweather to break his tradition and the Nevada State Athletic Commission's investigation could end Nurmagomedov's chances of returning to Las Vegas.
There's still a long way for the fight to go and it seems the location could prove a massive problem in any negotiations going forward.
That being said, you can't fault Nurmagomedov for effort and the offer is now there.
Do you think Nurmagomedov has any chance against Mayweather? Have your say in the comments section below.