'I should have taken his head off': Ex-UFC ace McGregor wishes he had shunned rules to break boxing great Mayweather's face & neck

Conor McGregor has claimed that the first shot he threw in his fight with Floyd Mayweather was "right on the button" and should have spurred him to a shock knockout win, adding that he remains "upset I fully followed the rules".

Former UFC lightweight champion McGregor admitted he had been drinking whiskey as he looked back on the fight, reflecting on his game first round as he came out firing in the first professional boxing match of his career.

Defensive specialist Mayweather smiled at McGregor and did not endure any notable damage during the opening round, but his old antagonist landed enough scoring shots to be ahead on all three judges' scorecards after the first three minutes in Las Vegas.

Now the MMA star turned boxer has described how he connected "inside the very first second of the fight", calling experts who questioned his boxing skills "bums" and telling his fans to "listen to none of them" ahead of his mooted return to the ring against Manny Pacquiao next year.

"I didn’t even put anything into that shot," he explained, describing his statement of intent against the undefeated middleweight champion in August 2017.

"Just placed it. Right on the button through the guard. Really, I should have just sat right through that shot and taken his head off and f*ck the distance.

"If it didn’t work out, just give him a good boot into the neck and get disqualified and fined and who’d give a f*ck?

"I’m upset I fully followed the rules for that fight, to be honest. Floyd deserved a volley, at the least. A shoulder even, break the face."

Fighting under boxing rules in an encounter that was considered intriguing by some and a farce by others, McGregor never recaptured the heights of that promising start, visibly tiring as the fight wore on before Mayweather ended his respectable challenge in the tenth round.

Addressing his following of almost 37 million on Instagram, McGregor conceded that he had attempted to conserve his energy in anticipation of a tactical battle with one of the smartest fighters in the history of boxing.

"It was hard for me not to dwell on the full 12 rounds that were potentially ahead of me and hold back my shots early," he said. "Still, though, right on the absolute button.

"Remember the experts saying I wouldn't land even one. I landed more than them all."

Mayweather was busier and more successful than McGregor during his comfortable victory, but the man who had switched disciplines landed more punches at a greater accuracy than Pacquiao did when he fought Mayweather two years earlier.

Hugely experienced champion Pacquiao was less successful than McGregor despite having two more rounds to attempt to break Mayweather down, but McGregor's feelings towards his stated next opponent are apparently less violent.

He said that could change should there be any more outbursts from Freddie Roach, the revered trainer who is likely to be in Pacquiao's corner for a fight that McGregor has said will take place in the Middle East.

Roach surprisingly took to social media on Saturday to warn that McGregor would be knocked out early by Pacquiao if they meet.

"Manny not so much though, I don't think," McGregor said after describing the brutal beating he wished he had inflicted upon their shared former opponent.

"But I will see how the build up goes and wait to hear what bitter old Freddie Roach has to say and then make a decision.

"I hope no bottling takes place here. I’m already agreeing to these limited rules and holding back my full array of weapons. Let’s get it going, guys."