But dig a little deeper and you’ll find plenty are asking: is it time UFC got over its obsession with McGregor?
The Crumlin native will again take on Diaz at welterweight at UFC 200 – UFC supremo Dana White wanted him to drop back down to 145 pounds or fight Diaz at 155 – while Jose Aldo and Frankie Edgar contest an interim belt as his absence from the featherweight division continues.
This seems to be exactly what McGregor wanted – but is it what the fans wanted? And is it what’s best for UFC?
Many fans feel this is simply the wrong fight for McGregor.
The 27-year-old was literally punching above his weight when he stepped up to 170 pounds earlier this month to take on Diaz when Rafael dos Anjos pulled out of their lightweight bout.
Clearly McGregor feels the need to prove himself in this new weight class – according to White he was “obsessed” with getting a rematch at 170.
But many people feel he won’t be able to prove himself because he simply isn’t a welterweight.
Some think McGregor hasn’t even proved himself at featherweight – he won his one title fight at the weight in 13 seconds against Aldo, and immediately set his sights on going up a weight or two.
Certainly his status as the sport’s biggest star is based as much on his gift for hyping himself up as it is on his achievements inside the octagon.
Before Ronda Rousey’s shock loss to Holly Holm at UFC 193, White believed the former women’s bantamweight champion was the biggest draw in combat sports.
Now that accolade surely belongs to McGregor – but because of his accelerated rise through the sport, the manner of his win over Aldo and his talent for self-promotion, question marks remain.
What, then, does he or UFC have to gain from the Diaz rematch?
Aside from anything else, the match-up leads to the bizarre spectacle of having Aldo and Edgar going for an interim title at a weight he has abandoned on the undercard of his own scrap against Diaz.
This is something that has really got under the skin of a lot of UFC fans.
If McGregor won’t defend his featherweight title, shouldn’t he vacate it? It seems disrespectful to have two fighters of the class of Aldo and Edgar going for an interim crown.
What does it say about the sport?
And what does it say about the power McGregor has that he is seemingly able to get whatever fight he wants?
Fans have been left with the impression that it’s all about the money.
And whether that’s true or not, the cynics certainly don’t have to look far for ammunition to back up their argument.
One thing’s for sure though – this is a fight that leaves nowhere to hide, either for McGregor or his critics.
Lose, and his image will be severely tainted – he will forever be seen as an Icarus character who did not know his own limits.
Win and he will justify the hype once and for all.