Conor McGregor tried and tried, and stirred and poked, and used every insult and low blow he could possibly think of. But as he broke his exile from public view and squared off against upcoming opponent Khabib Nurmagomedov at a media head-to-head in New York on Thursday, the Ultimate Fighting Championship superstar was unable to strike the kind of psychological blow he craved.

McGregor is a master at dismantling the mind-set of his rivals long before he faces them in the octagon. Yet Nurmagomedov, the unflappable Russian, refused to lose his cool as a typically bombastic and inflammatory McGregor spouted vitriol on a wild evening at Radio City Music Hall.

There was so much interest in the news conference that it was possible to place a wager with one online bookmaker about outcomes as diverse as whether McGregor would be chewing gum or if Nurmagomedov would wear his signature papakha hat.

The most obvious bet of the lot was that McGregor would utter more than 10 curse words. Easy, easy money.

Here is a look at the five most memorable exchanges over the course of a 39-minute to-and-fro dominated by McGregor’s mouth, with rants that mixed shameless promotion for his new whiskey brand with personal digs that tested the boundaries of ethnic decency.

1. McGregor blasts UFC for banning fans from event

Given the background between the two, most notably this year's infamous bus attack in which McGregor shattered a glass window by hurling a metal dolly, keeping Thursday’s occasion media-only was probably a smart move.

McGregor didn’t agree.

“I would have had the (expletive) fans in the arena, that’s who we fight for,” he said. “Bring me all over the world and have us just sitting here? You wanted a war, here we are, get a war going.”

UFC President Dana White had the final word on the matter, though.

“We have had problems in New York,” he deadpanned. “I didn’t want problems in New York today.”

2. Nurmagomedov’s quiet confidence

It is difficult, but not impossible, to beat McGregor inside the octagon. Three men have done it, most recently Nate Diaz in 2016.

Beat him at trash-talking? Forget about it. And so Nurmagomedov didn’t try, learning from mistakes made by previous McGregor opponents, who found themselves verbally bullied at such events.

When McGregor constantly tried to talk over him, Nurmagomedov often simply put down his mic and waited his turn. When a moment of quiet appeared, he made it clear that of all the men McGregor has faced, he might be the only one who truly believes he is going to win.

“I am going to put him back to (boxing),” Nurmagomedov said. “You cannot compete in wrestling. I am going to maul you. You come for money, I come for legacy.”

At the final head-to-head, with McGregor snarling in his face, Nurmagomedov did not flinch for a moment. Fights can’t be won at such times, but they can be lost. The Russian more than held his own.

3. White defends controversial promotional approach

Many have questioned the appropriateness of using the bus attack by McGregor and his cohorts as the central theme for the promotion for UFC 229. After all, women’s strawweight champion Rose Namajunas, who was a passenger on the bus, was severely traumatized by the experience. Two other fighters were injured by the shattered glass and ruled out of their upcoming fights.

White, however, was unrepentant. Asked whether it was a tough decision to formulate the promotion in such a way, he responded: “Not tough at all. It is part of the storyline, it is what it is. Things happened leading up to the fight, that’s how it played out.”

4. McGregor ramps up the verbal onslaught

Let’s face it, watching McGregor in full flow is darn entertaining, even if it is a guilty pleasure at times. But there were a handful of incidents on Thursday in which he came perilously close to overstepping the line. He tried to offer Nurmagomedov a drink of his new whiskey brand, Proper Twelve. After Nurmagomedov responded that he was a teetotaler (he's Muslim and his religion forbids drinking), McGregor sneered at him: “You backwards (expletive).”

McGregor also sailed close to the wind in discussing historic ethnic tensions between citizens of Chechnya and Dagestan (the Russian region from where Nurmagomedov hails). The issues in the area are complex and go back generations. While all might be fair in love and fight promotions, McGregor stepping into those realms could be seen as in particularly poor taste.

Finally, McGregor also highlighted the legal problems experienced by Russian tycoon and Nurmagomedov benefactor Ziyavudin Magomedov, an oil billionaire under arrest on embezzlement charges. Given the potential repercussions for crossing Russian President Vladimir Putin, Nurmagomedov could say little in response, and McGregor knew it.

5. McGregor hasn’t lost gift of gab

Even if McGregor's diatribes didn’t have the hoped-for effect, his two-year absence from the UFC hasn’t dimmed his ability to rattle off entertaining chatter at rapid pace.

The following exchanges lasted no more than 20 combined seconds, but formed a collection of crude poetry that was hard to turn away from. McGregor is one of the best fighters mixed martial arts has ever seen, but as a promoter, he is the undisputed champion.

“You are a little weasel,” he rapped, midway through the news conference. “A hard man in groups but on his own, when confronted, he cowers away. That what you saw with that little (expletive) on the bus, he (expletive) his jocks. I came for the love of fighting and the love of war and I will love to put a beating on this little glass jaw."

“I will stomp on his head as he is unconscious. It has been a war zone in my camp. I am preparing for war. Broken orbital bones, broken feet, broken fingers. You hold onto legs for dear life. You fight like a rat. What kind of way of fighting is that?”

Follow Martin Rogers on Twitter @RogersJourno