Leon Edwards' incredible head-kick knockout of Kamaru Usman was no happy accident, his striking coach Henry Cleminson has insisted.

The UFC welterweight champion locked horns with his predecessor at the summit of the welterweight division last weekend in the main event of UFC 278 in Salt Lake City.

Usman's bid to defend the welterweight title for the sixth time in a row ended in the fifth round of his rematch with Edwards, with 'Rocky' winning the contest via knockout thanks to a left high kick.

Afterwards, after congratulating Edwards on his victory, Usman described it as the perfect 'Hail Mary'.

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However, according to Cleminson, they planned for that exact moment during Edwards' training camp for his welterweight showdown with Usman.

Cleminson told MMA Junkie: “It wasn’t a technique that I think was going to be there early doors.

“Without going into huge details about what we’re doing, there’s a lot of strategy. We drilled a lot of things with that. You can’t just go and throw a head kick, especially early doors.

"He’s probably going to be fresh, reactions are high. I thought it was a technique that was going to land later on with some of the work he’d done throughout the fight. I thought I would see him throw caution to the wind earlier on, but it was something we were strategizing to set up.

Kamaru Usman was knocked out by Leon Edwards in their rematch

“I was pretty confident that Usman at some point was going to move away from the punch to that side, and Leon saw it. If you’re going to be ducking into head kicks, these things would happen. I’ve pulled up some video and cut some video footage of the Colby [Covington] fight, [Rafael dos Anjos] as well, and he does it numerous times.

"I’m like, ‘This is a pattern forming. I think you can manipulate this.’ It’s all about timing.

“It’s not easy. I’m not saying you can just throw it, and it’s going to land. You have to have a bit of an element of surprise and a bit of strategy and timing.

"All the pieces fell into place at the right time for Leon. He’s that good. He was able to time it perfectly, which not many people can.”

In fact, Edwards executed the move so perfectly, Cleminson says he doesn't think it will happen again. But he certainly won't be one to complain if it does.

He added: “I’ll say once in a lifetime.

“If it happens again, I’ll be a lucky person. I’ve been involved in a lot of fights, seen a lot of fights, and you’ve got fighters that perhaps might need a knockout or whatever, but how many times does that actually happen? How many times would that happen against the pound-for-pound No. 1 fighter in the world?

"Live on telly all across the world. It just doesn’t happen. It was certainly a once-in-a-lifetime kind of an experience.

“In the fifth round [the coaches] were both looking at each other like, ‘What’s going on? He doesn’t seem right.'

"So we were worried. But to be honest, Leon, you don’t count him out. I think he found it from somewhere.

"Fair play to him. It was certainly worrying, but in true Leon fashion, keeps us on our toes.”

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