Conor McGregor has vowed to avenge his defeat to Dustin Poirier when he takes on his past conqueror in a rubber match at UFC 264 in Las Vegas.

McGregor and Poirier were initially pencilled in for a high-stakes shootout this summer but a deal looked close to collapsing at any moment until UFC president Dana White confirmed the trilogy fight is now official for July 10.

'The Notorious' is the former UFC lightweight champion - a belt previously held by the recently retired Khabib Nurmagomedov - and is prepared to put his legacy on the line by taking on Poirier in just his fourth bout at 155lbs. 

McGregor (22-5), 32, finished Poirier, also 32, with punches at 1 minute, 46 seconds in the first round of their featherweight bout at UFC 178, before losing in a stunning upset at UFC 257 nearly seven years later.  

The Irishman may be a slight underdog with some bookmakers heading into this fight but has warned the former UFC interim lightweight champion that he is on a mission for revenge in a post on social media. 

'July 10th I will do this absolutely flawlessly,' McGregor wrote on Twitter. 'We have these clowns sussed and fully!

'They wanna play a game of tactics? No problem, see you in there.'

'You've awoken a beast. A beast with the backing of a much higher power!

'Say your prayers.'

Poirier, who improved his record to 27-6 (1 NC) by stopping McGregor in the second round back in January, responded by tweeting: 'Let hard work be thy medicine.'

McGregor and Poirier's rivalry is heating up nicely ahead of their highly-anticipated fight.

Poirier is currently in the midst of his training camp at American Top Team, where he is preparing for the upcoming war.

McGregor, meanwhile, has been putting in the work at the UFC Gym in Abu Dhabi. 

He's looking in incredible shape as he plots his UFC comeback.

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