Conor McGregor has congratulated Leon Edwards on his fifth round knockout of Kamaru Usman.

In a fight that many saw as little more than a formality, underdog Edwards knocked out the former pound-for-pound king Usman in the main event of UFC 278 at Vivint Arena in Salt Lake City in the early hours of Sunday morning.

Usman was heavy favourite to retain the UFC welterweight title against rival Edwards.

However, despite dominating for much of the fight, he found himself staring up at the ceiling at the end of the fifth round courtesy of a perfectly-timed head kick.

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McGregor, 34, posted on Twitter: "An amazing scene to witness!

"Huge congrats Leon! A real good, solid and dedicated mixed martial artist!

"The UK’s second only UFC champion! Incredible! Congrats mate!

Leon Edwards

Leon Edwards is the new UFC welterweight champion

"Not even a relatively high kick. Fully leaned into his own death.

"One leaned his way to victory. Another leaned his way to death. Crazy sport, I love!"

McGregor and Edwards are both managed by Paradigm Sports, the same talent agency which represents the likes of Israel Adesanya, Cris Cyborg and Stephen Thompson.

Edwards will now have a think about what's next, while for Usman it's back to the drawing board.

It's likely the pair will run it back in a trilogy fight at the earliest opportunity.

Speaking to ESPN, Edwards revealed how he wants to inspire others after capturing the title from Usman.

When asked what makes having the belt so special, he said: "Just my journey. The long hard road I took to get here. They all doubted me.

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"They all said he's finished. You've had two years out of the ring. You can't get your momentum back.

"They brought me in against the pound-for-pound best. I told everybody, the belt belongs to nobody, there is no pound-for-pound best. I believe that I was the better man and I proved it tonight.

"It wasn't my best performance, for some reason my body wasn't reacting the way it was in training.

"But it is what it is, I got a nice clean finish, and that's it."