The ring was still thronged as the rich people emptied out of their $10,000 seats, a fragrant train of the varnished and bejewelled, hurrying away towards the next evening curiosity. They looked pleased in the way of opera-goers exiting before a second encore.
The fight had been believable, a contest stretching further into the Nevada night than the majority had thought possible. And you had to think this was the Vegas of Bugsy Siegel's dreams. A gathering of money and darkness canyoned into some big Strip palace, millionaires and movie stars moving from one electric sign to another, like from The Flamingo to The Dunes, Sinatra to Dean Martin.
For this was, above all, a show. A piece of surreal, high-price entertainment.
The high rollers would be well over Conor McGregor by the time he made his own exit from T Mobile Arena, just after 12.40am in the back of a white Rolls Royce, wife, baby and a bottle of whiskey for company.
His bout with Floyd Mayweather won't ever quite reach a boxing museum and maybe, in time, it will be remembered less as a sports event than some extravagant tourist attraction. Certainly, the idea that boxing might suddenly have to sit up at McGregor's command was left coldly unwrapped as a silly conceit.
Once a 40-year-old Mayweather settled into the beat of things, his ringcraft reduced the Irishman to a picnicker swinging at a wasp.
But the fight stats told us that he'd landed 111 punches on a boxer of such uniquely skilful defence that opponents ordinarily end up feeling like drunks chasing bank notes in the wind. For a debutant in this school, that had to be something.
Now it must be said that not everybody bought the message implicit in those figures. Some at ringside suspected Mayweather had maybe been playing games, if only to hold a parody together. That with so much money spent, they couldn't be seen to allow the sands of this fight run out too soon.
Who can say?
McGregor won the first three rounds on most cards, including that of judge, Dave Moretti. The other judges, Burt Clements and Guido Cavalleri, had the fight scored eight rounds to one in Mayweather's favour before McGregor was rescued from the American's whistling gloves just over a minute into round 10. By then, McGregor was just pawing into a blur of leather, his head snapping back far too often even for the taste of the most blasé paying customers.
And, as we knew it would, the end decommissioned what had been a pageant of vulgarity. By the time McGregor joined Mayweather at the post fight press-conference, a glass in one hand, a bottle labelled 'Notorious Irish Whiskey' in the other, the two fighters had taken to spontaneous hugging and fist-pumping.
Mayweather, dressed in black tracksuit with gold spangles, talked of being "kinda shocked" by how good McGregor had been. And the Dubliner, in floral blue suit, paid tribute to his opponent's ability to "change gameplan three times" which, of course, is "what a true champion does".
Both came to the press conference then, bubbling with vindication. Thanking the suits, counting their cash, moving on.
And the pre-occupation with money was understandable. McGregor was still speculating that he could clear $100 million for the show, telling us, "We're now in the counting phase! I've sent auditors in there like f*****g sharks to count every single dot."
Mayweather was hoping, it seemed, to do maybe twice that, reminding us that he'd got sponsors who'd stump up "millions" for just half an hour of his attention.
From start to finish, the whole gig made you feel as if you were sitting in on some bizarre movie set.
In its starkest terms, this was a fight with no basis in logic. A debutant looking to make a mockery of boxing against somebody once considered the best pound-for-pound pugilist on the planet. Mayweather, who would remind us that he'd been "a millionaire by 20 or 21" against McGregor who, as John Kavanagh recalls, could not draw "a sponsor for a tub of protein" until the UFC tuned into his charm.
McGregor's MMA instinct to grapple his opponent from behind, to chop down on the back of his head, to essentially fight dirty, kept drawing him into territory that required the referee's intervention.
Yet his right-hand jab was working too (28% accuracy to Mayweather's 31%) and that left-hand always seemed cocked as if ready to deliver some kind of wrecking-ball moment. Trouble was, in time, Mayweather's shifting feet kept taking him to places McGregor couldn't reach
By the seventh round, he landed a succession of heavy, right-hand crosses that drew uncomfortable gasps. And, when the stoppage eventually came three rounds later, it was less an intervention of pity than an act of common sense.
McGregor, inevitably, did not think so. He talked of being fatigued, but clear-headed. "It was a little early," he told us. "I get a little wobbly when I'm tired. But get me in the corner and I'll recover and I'll come back. He (the referee) should have let me keep going until I hit the floor.
"Let me go down. Let the man put me down. Wobbly or fatigued, that's energy, that's not damage. I'm clear-headed. Let me wobble back to my corner. Let me try to compose myself. You've got to put me out.
"If that was a Mixed Martial Arts bout, you'd want to see your nose hanging off your face before you're even considered getting stopped like that. You know what I mean? There was no knock-down, no nothing. And they stopped it. That never happens in MMA. It is what it is ..."
He tried to make the distinction between "glancing" blows and "damaging" blows, maybe between optics and reality. "You know what? I don't feel like I lost a fight," McGregor said. "I feel like I lost a football match or something.
"I caught him with a few big shots early on, then I started to waste energy. It was a very enjoyable experience and a great learning experience."
As he spoke, McGregor's wife fed their baby son a midnight bottle, surrounded by a posse of Mayweather's faction, the two tribes now purposefully at peace. It hadn't been a full house on the night, nine of the highest storey sections left empty as many chose to watch from cheaper vantage points in bars and casinos.
Had it all maybe been some kind of spectacular ruse?
"A lot of people thought it was fake," acknowledged Mayweather. "But we didn't like each other.
Probably still don't like each other.
"He's a lot better than I thought he'd be. He's a tough competitor. He was a hell of a fighter staying up, kinda shocked me.
"Tonight was my last fight. Tonight I chose the right dance partner to dance with. Conor you are a hell of a champion."
Naturally, it was impossible to reconcile such civility with the ugliness that went before it, but Vegas isn't a town that ever gets too bogged down on the business of advertising standards.
"Any regrets?" somebody asked McGregor.
"Absolutely none," he replied, an arm around his mother Margaret. "This was some buzz, to come in and face this man with so many doubters. If it was me looking back, it's a young kid that came from nothing, came to take it all. And you know, I came up short tonight, but it is what it is.
"I just hope that the people were entertained by the whole thing, from the mental side of it, from the verbal side of it and, of course, from the final, physical side of it. Because there was many forms to the fight, the verbal battle on the world tour, the mental battle through the whole thing and, of course, the final physical.
"It took me aback to come from the game I come from and be disregarded and disrespected like that. You've got to be iron tough in this business if you want to face that type of criticism. There was a lot of disrespect and disregard for my skills, I was a little bit taken aback ...
"In fairness Floyd and his team never actually showed that disrespect. But just the overall ... everyone else, it was almost like a little bit of a jealousy thing. So I kind of just got over it..."
By now, burly security men were becoming impatient to empty the arena. "We gotta get Conor outta here," screeched someone's walkie-talkie. But 'The Notorious' kept stopping to talk, kept smiling and sipping his whiskey, kept harvesting the platitudes of a media still holding on to every word as if, at some point, he might spontaneously combust.
Would he do it again?
"Yeah, I believe I'll do it again," he shrugged. "But I'm looking forward to kicking something again first." And then he was off in his white Roller, away to some gilded party maybe with J Lo or Le Bron.