In a spin: UFC star ends fight with spectacular spinning backfist – then suggests poleaxed opponent should be given bonus (VIDEO)

Beneil Dariush made up for missing the weight for his lightweight contest with Scott Holtzman by providing a brutal first-round finish, leaving his opponent flat out on the Octagon floor by executing a perfect spinning backfist.

Lightweight Dariush had already landed a shuddering knee when he stunned veteran foe Holtzman with a forearm that left the 36-year-old requiring help to rise uneasily to a stool minutes after their contest at UFC Vegas 6 had finished.

Holtzman had predicted a lengthy slugfest on Saturday, only to be laid out with 25 seconds of the opening round remaining as former Jiu-Jitsu champion Dariush secured his fifth straight victory.

Dariush admitted he was embarrassed at weighing in two pounds over the 156lb limit, suggesting that Holtzman should be given the potential $50,000 bonus he was ineligible for as a result.

"If that was performance worthy, give it to Scott," said the Assyrian-American. "I think that's the best thing to do.

"I missed weight so I don't deserve it. He came for the kill.

"I'm not trying to sound cocky but it's not like he was taking an easy fight.

"That was basically 50/50. I wasn't always like this. Sometimes it just happens – I forget everything and just do stuff."

The eighth spinning backfist knockout in UFC history was the fourth consecutive premature end enforced by Dariush, extending his unbeaten streak to almost three years.

He took an extra round to show his knockout power in his previous encounter at UFC 248 in March, when he sent Drakkar Klose to the canvas with a punishing flurry of punches.

Asked why he had not followed up his fight-ending shot against Holtzman, Dariush said: "The same thing happened with the fight before – I just didn't feel like it was necessary.

"If the guy's eyes are rolling back...it just didn't make sense to me."