Maybe the diversion was worth it after all - the rematch that drove the rebuild.

In the more usual fighting terminology of a not-too-distant past, the second meeting of Conor McGregor and Nate Diaz last Saturday night would have been labelled Diaz-McGregor II.

The world of mixed martial arts and particularly its leading organisation relentlessly - often needlessly - eschews the normal or the customary, however. So it was that the second coming together of featherweight and lightweight at a whole other weight became Diaz-McGregor 2.0.

As the air thinned out again late Sunday evening in Las Vegas, thoughts turned back to that latter label. More specifically the thought that, given what had taken place at the T-Mobile Arena the night before, if you shaved away Diaz's name and dropped the dash too, you'd be left with what could be the lasting legacy of an utterly arresting, absorbing night - McGregor 2.0.

The main event of UFC 202 had been a corrosive classic that pared back so much of both men and revealed a new ‘Notorious’.

The ultimate dogfight, McGregor had in the first phase been pedigree (expected) and when dragged deeper - deeper than ever before - become mongrel (wholly unexpected).

Most of all, the promoter, the dealmaker, the game-changer was a fighter again - an altogether different fighter.

In fact in securing revenge with a marathon majority decision win, he became exactly the kind of fighter that fighters themselves doubted he could be.

"I don't know if Conor McGregor has a style that can go five rounds," Dominick Cruz, the UFC's two-time bantamweight champion and one of its most agile bodies and minds, had told analyst Joe Rogan on fight night.

Given the brutally breathless nature of Saturday's bout, it paid to take it in again in the colder light of the day after on a TV replay. That's where Cruz's suspicion - widely held by many of McGregor's compatriots - had been expressed.

The technical retuning of McGregor - led by his coach John Kavanagh - has by now been well pored over, so many of the wrongs of the first fight in March being righted. What's pressed home again on second viewing is just how pivotal the 28-year-old's physical and especially mental changes were too.

One moment from the broadcast stands out. "Conor is fading rapidly," Rogan roars in the third round as Diaz himself roared back into the contest, the man on the mic labelling McGregor "a much diminished fighter" now.

Yet as the pair go into the clinch against the cage, Kavanagh assures his charge he's fine there. Both are calm in unchartered waters.

"Gone is the wild and the maniacal, replaced with a cold, hard focus that never really slipped"

McGregor adjusts, little by little, eventually weathering an almighty late storm to survive the round and then turn the tide again early in the fourth. It never turned back. The marrying of all three fresh approaches - technical, physical and mental - is what got the job done.

Many observers have astutely zeroed in on the perceptible differences in McGregor's pre-fight approach Saturday that signalled towards this new version of the Notorious.

The split-screen contrast of his ring walks from the first and this second Diaz fight is the kind of thing a behavioural analyst would feast upon. Gone is the wild and the maniacal, replaced with a cold, hard focus that never really slipped.

But what's just as striking is how differently he was tuned in the aftermath of the triumph too. Looking over even our own rough transcripts of the post-fight press conferences from Saturday night and his most recent victory to that, the change-up in tone and tenor is marked.

After December's stunning 13-second evisceration of an icon in Jose Aldo Jr, every second offering from McGregor concerns dollars and his perceived dominance over all.

On Saturday night, in the less salubrious surrounds of a makeshift media tent in the car park of the T-Mobile Arena - press facilities have yet to be completed at the new sporting home of the Strip - McGregor was significantly less bombastic.

That may have been circumstantial, but only very slightly.

He referenced purses just once - without specifics - in a blast about how he had been doubted. But the overwhelming majority of his offerings are those of a fighter, not a promoter. The numbers he speaks of concerned weights, strikes, knockdowns, not fees, gates and pay-per-views buys.

McGregor spent Saturday night and Sunday afternoon fulfilling his post-fight nightclub and pool-party obligations. The obvious question now that things quieten down is what this recasting means for the next step and the ones after that.

We wrote in this same space after the Aldo victory the answer to 'what's next?' was 'whatever the hell McGregor wanted'. It's arguable that that's the case all over again as he ponders the rubber match with Diaz, a drop down to lightweight to take on champion Eddie Alvarez or his least favoured for now, a defence of his featherweight title.

Having been chastened in defeat and victory in and out of the octagon in the intervening time since he last fought Aldo, McGregor shapes to be more careful with what comes next though, even if you flick back through those notes and recall that his closing words on Saturday night were "the sh*t's about to hit the fan".

There is no denying that in his slow, slow then rocketing rise to the top of combat sports and gatecrashing of the mainstream, McGregor has already undergone numerous transformations. There'll likely be more.

Yet in the next phase of the journey the Nate Diaz diversion that has bred McGregor 2.0 might just be the most transformative.