Irish fans roar on Conor McGregor against Floyd Mayweather at raucous weigh-in ahead of Saturday's fight

The travelling Irish support have taken over the city of Las Vegas ahead of McGregor's fight against Mayweather, and made their voices heard at the raucous weigh-in

The pair went face-to-face in front of a raucous, predominantly Irish crowd (Getty)

The first sign that Las Vegas was preparing for imminent invasion came at the start of the week, when a handful of bars stuck small, not entirely inconspicuous stickers on their front windows, proudly advertising that they sold Guinness on tap.

Shortly after, the Irish pubs dispatched a horde of temporary workers to blanket the sidewalks with endless flyers, containing similarly endless drinks offers. By Thursday, they impatiently jostled for position down the Strip with the street vendors, who had started flogging large flags of green, white and gold along with their hastily printed t-shirts and snide ‘The Money Team’ snapbacks.

And then on Friday — en masse and seemingly overnight — they finally arrived. Thousands of Irish fans wearing an eclectic mix of emerald soccer, rugby union and Gaelic football jerseys. Some drunk, most drinking and all heading directly for the T-Mobile Arena, in plenty of time for Friday afternoon’s weigh-in.

Additional security checks at the 20,000-capacity venue meant that, having strolled out of the dimly-lit New York-New York Casino and into the full glare of the unrelenting desert sun, the sea of Irish fans was made to congregate on the Toshiba Plaza outside. From there they trickled in smaller numbers towards their seats which, in what must be a first for this city, had been available for free.

It all made for a relatively unique pressure-cooker atmosphere. 90-minutes before their idol was due on stage, one small cluster of emerald began the Olé, Olé, Olé chant, which slowly — steadily — rose in volume, as more sun-burnt supporters staggered into their seats.

Mayweather Promotions had kindly laid on entertainment ahead of the theatrical weigh-ins, but it wasn’t needed. This was a crowd content to entertain itself, with the singing replaced by deafening cheers when — with entirely uncharacteristic punctuality — Conor McGregor appeared from the bowels of the Arena and bounced his way towards the scales at 3pm sharp.

McGregor's weight cut had clearly taken its toll (Getty)

Were it not for the flag draped round his neck and the impressive size of the posse around him, it would have been forgivable to mistake McGregor for a completely different man, perhaps one of the lesser-known fighters on the undercard. The heavier, healthy McGregor from the start of the week was long gone — replaced by a taut, gaunt man who maniacally screamed down the camera lens when on the scale and furiously beat his chest when his weight was read back to him.

“153 pounds.” One pound inside the limit.

Floyd Mayweather couldn’t help but smirk when the Irish were briefly drowned out by the opening seconds of In the Air Tonight by Phil Collins, before the booing became so loud that the broadcasters on Fox began shooting nervous looks at their clipboard-wielding producer. Well attuned to playing the heel, Mayweather shuffled his way towards the stage, speeding up only for the final few paces, skipping past a snarling McGregor like a child taunting a chained dog.

The pantomime didn’t end there. Shedding his elite leisurewear, the jeers intensified when it became clear Mayweather was wearing emerald-green pants and socks, emblazoned with a certain bookmakers logo. Hopping onto the scales, he lifted his head to the heavens as his weight was announced to the world.

“149-and-a-half pounds.” Four-and-a-half pounds inside the limit.

This fight has already contained more moments of pure theatre than a night on Broadway, and yet the reading of Mayweather’s weight contained more drama than all of them put together. The crowd let out a collective gasp. Mayweather laughed. And McGregor went on the offensive.

Mayweather revels in playing the villain (Getty)

“He looks like dog s**t,” McGregor said, to a laugh so loud it would have made even Billy Connolly blush. “You know that, he looks blown out. Full of water. He’s not gonna keep my pace. Trust me on that. That’s the worst shape I’ve ever seen him.”

Mayweather has spent much of the past week taunting McGregor over his weight (even suggesting — with zero evidence — that he had been illegally using IV bags in a panicked attempt to make the cut) and now it was the Irishman’s turn to wage war on his opponent’s waistband. “I’m going to be a lot bigger than him by tomorrow,” he solemnly warned. “I’d say I am going to be close to 170 pounds.”

Was Mayweather worried? Was he heck. “I've been here before, I know what it takes to win a fight of this magnitude,” he said, striving so hard to come across as unflustered that he instead came across as being bored. “Weight doesn't win fights, fighting wins fights.” Which is true: except that 20-pound weight advantages certainly make winning fights more difficult.

After a quick face-off they were done. Both were shepherded off stage quickly, McGregor holding a protein shake that had been hurriedly pressed into his hand the moment the pre-fight pleasantries had concluded. But the fans did not leave so rapidly, some choosing to remain in their seats happily flicking v-signs at Mayweather’s family, the others holding fort in the atrium, singing and dancing in front of a minority of confused Americans.

Eventually the small army of security guards grew tired, prizing fans from their seats and showing them all the door, thus concluding one of the most divisive, drawn-out and downright controversial pre-fight programmes in the history of boxing. And that sea of emerald swept down the street and into the nearest casino, still singing. The weigh-ins were over but the party was only just beginning. Whether any Irish eyes will stay smiling an evening later remains to be seen.