WATCH: The moment when Nate Diaz knew he had Conor McGregor beaten

This is the moment when Conor McGregor's world came crashing down.

The UFC featherweight's aura of invincibility in the octagon was burst in spectacular fashion by Nate Diaz in Las Vegas and it all began with one clinical straight left from the American. McGregor had dominated the opening round and a half of the fight, his left fist leaving the right side of his opponent's face a bloody mess. But Diaz appeared to be waiting for his chance, and when the moment came he seized it ruthlessly. He landed clean on McGregor's jaw to stagger the Notorious and the Dubliner never recovered, getting caught multiple times before a desperate dive to the mat led to Diaz claiming victory with a rear naked choke. Here's that punch, and you can tell from Diaz's reaction that he knew it was now game on.