Here's a brief recap of tonight's events as we bring our coverage to a close.
Conor McGregor's much-anticipated return to the octacgon ended in defeat as he had no answer to a flurry of punches from Dustin Poirier.
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You can also click here to listen back to the BBC Radio 5 Live commentary as Poirier avenged his defeat at the hands of his opponent seven years earlier.
Afterwards, the 32-year-old American claimed he was now the "champion of the lightweight division", while McGregor said he is "heartbroken" at the defeat, but wants to keep on fighting.
In the co-main event, American Michael Chandler was impressive on his UFC debut as he beat New Zealand's Dan Hooker in the first round.
And Scotland's Joanna Calderwood earned a unanimous decision victory over American Jessica Eye on the undercard.
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'I was an assassin tonight' - Poirier
Here's some quotes from Dustin Poirier's post-fight press conference.
“This win is right up there. This is a big one. But I want to
put my hand on the undisputed title when it’s all said and done," said Poirier.
“Tonight is one of the best I’ve ever felt. I was
emotionless, I was an assassin, and I was here to execute. It feels good.”
“A rematch with Conor interests me. I’ve always wanted to [fight]
Nate Diaz. That interests me. I’m sure something will make sense but right now
I don’t know.”
Conor McGregor has just been speaking in the post-fight press conference.
“It’s heartbreaking, it's hard to take. The highest highs
and the lowest lows in this game,” he said.
“My leg is completely dead, and even though I felt like I was
checking them [Poirier’s leg kicks] it was just sinking into the muscle at the
front of my leg.”
“Dustin fought a hell of a fight. I thought I was better
than him in the clinch, but too little too late.”
“My leg was compromised and I didn’t adjust and that’s it,
fair play to Dustin.”
“I’m very happen for him and very happy I got to come back
and compete in my 11th UFC main event.”
“I don’t know where I’m at the minute to be honest.”
That win for Dustin Poirier surely earns him another shot at the lightweight title in his next fight, but who against?
As it stands, Khabib Nurmagomedov is still the champion despite retiring, and has not confirmed whether he will return or not.
Other names in the frame are Michael Chandler, who earned an impressive win tonight over Dan Hooker on his UFC debut, and Charles Oliveira, who is third in the rankings.
As for Conor McGregor, where does he go from here?
A trilogy fight with Nate Diaz? A boxing bout with Manny Pacquiao?
“Poirier has got to be the number one in the division, he’s got TKO wins over Justin Gaethje and Conor McGregor - he will be more hungry than anybody to run that
fight back with Khabib."
"He had to go away after the defeat by Khabib last time and
he realised there’s a whole new level to this sport.
“He’s in the right mind frame, he’s the number one in the
division and I’m so excited for what comes for him next."
Live Reporting
Paul Battison, Ben Collins and Frank Keogh
All times stated are UK

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Latest PostPoirier stuns McGregor at UFC 257
Here's a brief recap of tonight's events as we bring our coverage to a close.
Conor McGregor's much-anticipated return to the octacgon ended in defeat as he had no answer to a flurry of punches from Dustin Poirier.
You can also click here to listen back to the BBC Radio 5 Live commentary as Poirier avenged his defeat at the hands of his opponent seven years earlier.
Afterwards, the 32-year-old American claimed he was now the "champion of the lightweight division", while McGregor said he is "heartbroken" at the defeat, but wants to keep on fighting.
In the co-main event, American Michael Chandler was impressive on his UFC debut as he beat New Zealand's Dan Hooker in the first round.
And Scotland's Joanna Calderwood earned a unanimous decision victory over American Jessica Eye on the undercard.
'I was an assassin tonight' - Poirier
Here's some quotes from Dustin Poirier's post-fight press conference.
“This win is right up there. This is a big one. But I want to put my hand on the undisputed title when it’s all said and done," said Poirier.
“Tonight is one of the best I’ve ever felt. I was emotionless, I was an assassin, and I was here to execute. It feels good.”
“A rematch with Conor interests me. I’ve always wanted to [fight] Nate Diaz. That interests me. I’m sure something will make sense but right now I don’t know.”
Poirier vs McGregor 3?
McGregor is 'heartbroken'
Conor McGregor has just been speaking in the post-fight press conference.
“It’s heartbreaking, it's hard to take. The highest highs and the lowest lows in this game,” he said.
“My leg is completely dead, and even though I felt like I was checking them [Poirier’s leg kicks] it was just sinking into the muscle at the front of my leg.”
“Dustin fought a hell of a fight. I thought I was better than him in the clinch, but too little too late.”
“My leg was compromised and I didn’t adjust and that’s it, fair play to Dustin.”
“I’m very happen for him and very happy I got to come back and compete in my 11th UFC main event.”
“I don’t know where I’m at the minute to be honest.”
Post update
What happens next?
Get involved #bbcufc
That win for Dustin Poirier surely earns him another shot at the lightweight title in his next fight, but who against?
As it stands, Khabib Nurmagomedov is still the champion despite retiring, and has not confirmed whether he will return or not.
Other names in the frame are Michael Chandler, who earned an impressive win tonight over Dan Hooker on his UFC debut, and Charles Oliveira, who is third in the rankings.
As for Conor McGregor, where does he go from here?
A trilogy fight with Nate Diaz? A boxing bout with Manny Pacquiao?
Let us know what you think via #bbcufc
Khabib to stay retired?
The Eagle has landed...
'McGregor will be back'
Danny Roberts
British UFC welterweight fighter on BBC Radio 5 live
"He’s not an old dog, he's definitely ready to keep going."
"Going around doing other things is not what Conor needs. He's young, fit and still ready to go."
“He’ll 100% be back.”
Post update
Nick Peet
MMA journalist in Abu Dhabi on BBC Radio 5 Live
Dustin Poirier got rid of a few demons in there. He overcame the barrage of shots from Conor McGregor and then he stepped forward and got the finish.
'This was Dustin's time'
Danny Roberts
British UFC welterweight fighter on BBC Radio 5 live
It was Dustin's time, his moment. All that emphasis, he fully believed in his head and he's walked away with the victory.
Post update
Post update
That was the first KO/TKO of Conor McGregor's MMA career, according to ESPN journalist Ariel Helwani.
The Diamond brought the hot sauce tonight.
Post update
'Poirier is number one in the division'
Nick Peet
MMA journalist in Abu Dhabi on BBC Radio 5 Live
“Poirier has got to be the number one in the division, he’s got TKO wins over Justin Gaethje and Conor McGregor - he will be more hungry than anybody to run that fight back with Khabib."
"He had to go away after the defeat by Khabib last time and he realised there’s a whole new level to this sport.
“He’s in the right mind frame, he’s the number one in the division and I’m so excited for what comes for him next."
Post update
'I'll dust it off and come back' - McGregor
Poirier beats McGregor
"His leg kicks were good, my leg was dead and I wasn't as comfortable as I needed to be," says the beaten Conor McGregor in his post-fight interview.
"I have to dust it off and come back and that's what I'll do.
"I'm gutted, it's a tough one to swallow, I just want to go back to the hotel and chill with my kids and regroup."
'I'm the champion now' - Poirier
Poirier beats McGregor
"I think this was a title fight - I'm the champion now," says Dustin Poirier in the post-fight interview.
He goes on to say he's the best boxer in the UFC, referring to his two victories over Max Holloway.
It's hard to disagree after that performance.
Post update
Danny Roberts
British UFC welterweight fighter on BBC Radio 5 live
McGregor has a sense of being able to dictate the fight and he was up, but Dustin put him away.
I don't think the motivational purpose changes, although the meal ticket is not as big now for McGregor.
Post update
Poirier wins in round 2
McGregor is all smiles following the fight and there's a nice show of respect between the two fighters.
Poirier has his revenge seven years after defeat to McGregor.
An incredible performance from the Diamond.