Conor McGregor reacts after being knocked out by Dustin Poirier

The Irishman famously won the first fight between the two back in 2014 but had no answer in the rematch as the American enacted his revenge

Conor McGregor says he is “gutted” after being stunned by Dustin Poirier at UFC 257.

The Irishman famously won the first fight between the two back in 2014, but despite starting the stronger six years on, had no answer as Poirier blitzed him with a vicious combination of shots to send him tumbling to the canvas.

Referee Herb Dean soon waved matters off leaving McGregor to reflect on one of the more damaging defeats of his illustrious mixed martial arts career.

“It’s hard to overcome inactivity," McGregor said afterwards, this fight being his first in 12 months following his victory over Donald Cerrone a year ago. "The leg kicks were good, my leg was dead. I just wasn’t as comfortable as I needed to be.

“Dustin’s some fighter. I have to dust it off and come back. I need activity. You don’t get away with being inactive in this business.

“I’ll take my licks. I’m gutted. It’s a tough one to swallow. I put in a lot of work. I’m gonna get home to my kids at the hotel and just chill for a bit.”

McGregor and Poirier met for the first time in September 2014 as featherweights, and McGregor won by knockout in just 106 seconds during his incredible early-career success. 

McGregor became the featherweight champion 15 months later, while Poirier rebuilt his career with just one loss in his next 11 fights.

With a second chance to derail McGregor while boosting his own hopes of regaining the lightweight title, Poirier didn't miss.

Sporting a shaved head and a beard, McGregor pushed the action early against Poirier, who landed an early takedown before getting backed against the cage for stretches of the first round. 

In the second, Poirier bothered McGregor with leg kicks before throwing the punches that ended it. 

AP contributed to this report