Conor McGregor has vowed to build the UFC into a billion-dollar business

Conor McGregor vows to build the UFC into a billion-dollar business and Holly Holm makes her first defence of the title she won in spectacular fashion from Ronda Rousey as mixed martial arts grabs the spotlight in the Nevada desert.

Despite the fact that Rafael dos Anjos was forced to pull out of his lightweight title bout with McGregor on Saturday, the UFC is still expecting a bumper weekend as the Irishman instead steps up two divisions to battle Nate Diaz at welterweight.

The cancellation of the title fight with Dos Anjos should have dealt a serious blow to ticket and pay-per-view sales for Saturday's UFC 196.

Instead, the decision by the cocky, charismatic McGregor to step up to welterweight to fight Diaz has opened up a myriad of possible title shots.

If McGregor wins he will be well-placed to challenge welterweight champion Robbie Lawler; if he loses, there is always the Dos Anjos belt at lightweight up for grabs.

Adding to the excitement is the return to the octagon by Holm, who caused one of the UFC's greatest upsets when she sensationally knocked out previously undefeated Rousey to snatch the world bantamweight title from her last November.

Holm makes her first defence of that title against Nevada-based Miesha Tate, with Rousey waiting in the wings for a shot at taking her title back.

With intrigue stretching across the divisions of the UFC, the stage is set for continued growth in mixed martial arts.

Having enjoyed a haul of an estimated $600m in 2015, thanks in no small part to McGregor's fights, the UFC is expecting more than a million pay-per-view sales for UFC 196.

Asked at a press conference ahead of the fight if he could be the man to break the billion-dollar barrier for the UFC, McGregor was adamant.

"One hundred per cent. I am that man. I am THE man," he told reporters.

"If you look at the analytics, the evidence, the numbers are all going up. All the channels, all the platforms, the numbers continue to rise."

Whatever direction McGregor's career takes after Saturday's bout, UFC boss Dana White said he will be happy to accommodate him.

"I'm open to whatever he's considering doing. If he wants to fight at 170 (pounds) and he wants to fight Robbie Lawler? Conor is tough to deny these days."