Abdirzak claims he and friends were waiting for their car in the car park of the Fontainebleau Hotel when they saw McGregor leaving the same establishment.
They called out to the 30-year-old former lightweight champion and it appeared to be a perfectly cordial conversation until McGregor started mocking Abdirzak and his friends.
"My friend spotted him on the way out and shouted to him 'McGregor, McGregor, we've come all the way from London,'" he said.
"He turned to him and gave him a salute. I said 'Man dem McGregor' and he repeated it word for word, mocking me.
"It seemed good-natured at that point though, he seemed friendly. I wasn't insulting him or antagonising him at all.
"I don't drink, I've never touched alcohol in my life. I've never done drugs. I was completely sober."
Abdirzak claims it all changed when McGregor noticed he was filming the conversation on his phone, standing more than 5m away from the UFC star.
"He reached out his left hand to greet me, to shake my hand. But then he held my arm so I couldn't get away," the alleged victim said.
"His grip was insane. I could tell he was a professional athlete. I thought he's going to hit me. I was shocked.
"I looked into his face and his eyes were bulging. He was so angry. I don't know whether he was drunk or on drugs, but he looked f***ked.
"I just remained passive, I didn't want to fight. Then with his right hand he punched the phone. It was so hard I felt the impact through my entire body."
He claims McGregor picked up the phone before he could get to it and then proceeded to smash it.
"He stamped on it four times," the witness claims.
"He then picked it up and put it in his jeans. I couldn't believe what I was seeing.
"He did his swagger dance and headed to his black SUV with his entourage surrounding him.
"I was asking them, "Can I get my phone back?"
"I tried to run after him and asked for it back but he just laughed."
He says neither police or McGregor have been in contact to discuss the whereabouts of his phone and he remains angry that it has not been returned to him.
He also wants justice done so that McGregor should not be allowed to return to the United States or to receive a United States VISA because of his criminal rap-sheet.
"He's a dangerous thug, very dangerous," Abdirzak said.
"He lives up to his name — notorious. He thinks the normal rules don't apply to him.
"I wouldn't wish jail on anyone, but they should make an example out of him. His fans are already posting threats and jokes about me online."
Abdirzak earlier claimed the loss of irreplaceable photographs of his son is what "pisses him off most".
In a video released by TMZ, Abdirzak has given his version of events.
"We ended up at LIV on a Sunday," he said. "(American rapper) Blueface was there so we were just seeing what was popping. There were quite a few A-list celebrities over there, Birdman (another rapper), Blueface, NFL and a few NBA players over there.
"So we see McGregor in the club and it was all cool or whatnot. On the way out, we were just waiting for our vehicle from the valet. As soon as we go pick it up, I see Conor McGregor. So I tried to take out my little phone.
"As soon as I pull out my phone, McGregor comes and he tries to shake my hand. As soon as he went to shake my hand he pulled me in, grabbed my phone and started smashing it.
"All of his security guards literally surrounded me, pushed me out of the way. And he's stomping on it, there's a video that will be released soon. He was being real rude like, 'Get the f*** out of my face, you don't just do that.' So I was like, 'Sir can I have my phone back?' And there was all of his security and entourage around him. I just kept asking if I can have my phone back. They were like, 'Move man, move, you better listen to what Conor say'.
"McGregor then picked up the phone and put it in his pocket, laughed and then he got in his SUV and they drove off. That's when the hotel manager came. I got pictures of my son that I didn't even save to my iCloud, so that's what pisses me off the most. Those pictures I am probably not going to ever get again."
McGregor, 30, was arrested later at another address and charged with strongarm robbery and misdemeanour criminal mischief. His case will be heard in the Circuit Court in Miami-Dade County on April 10.
The former featherweight and lightweight world champion attempted to clear his head after his latest controversy by immediately going for a run after being released on bail.
McGregor was released on bail and was pictured smiling as he left a police station in Miami dressed in a grey top with grey tracksuit bottoms and dark sandals.
His T-shirt read: "When I say something is going to happen, it's going to happen."
He later took to Instagram to tell fans that he "continues to work" on his patience.
Sharing a snap, he posted: "Patience in this world is a virtue I continue to work on. I love my fans dearly. Thank you all."
McGregor has been on holiday with family in Florida to celebrate mum Margaret's 60th birthday.
His lawyer Samuel Rabin told the Miami Herald the Irishman "was involved in a minor altercation involving a cell phone that resulted in a call to law enforcement. Mr McGregor appreciates the response of law enforcement and pledges his full co-operation".
The Sun reports McGregor appeared animated with another clubber in footage posted online before his arrest in Miami.
In the footage posted on Instagram, McGregor — dressed in a dark t-shirt — is seen with another nightclub goer at LIV club in Miami.
He appears animated with the unknown clubber before the camera turns away.
It's thought the footage was filmed before the alleged incident in the early hours of Monday morning outside the Fontainebleau hotel on Miami beach.