LAS VEGAS — Conor McGregor is a featherweight champion fighting a lightweight at the welterweight limit at UFC 196.

When McGregor meets Nate Diaz at the MGM Grand Garden Arena on Saturday, the Irish brawler is taking on a challenge that would seem impractical, dangerous or downright ridiculous to most athletes in weight-dependent sports.

McGregor only cares about the fans' desires and the financial rewards for his boldness. They're more than enough to keep him doing the improbable.

"There's a lot of people that play it safe in this game," McGregor said at Thursday's news conference, shortly before getting into a brief scuffle with Diaz at the staredown.

"There's many scared (people) in the fight game, if I'm being honest," McGregor added. "They don't take risks, and people who don't take risks will never climb to that next level. I take risks all the time. Every single fight, I've taken a risk."

McGregor (19-2) is in this unlikely situation because lightweight champion Rafael Dos Anjos dropped out of their scheduled meeting with a foot injury less than two weeks ago. A disappointed McGregor ripped Dos Anjos for his caution, which prevented McGregor from attempting to add that 155-pound belt to the 145-pound strap he won in December by stopping long-reigning champ Jose Aldo in 13 thrilling seconds.

Although he had ample reason to drop off a pay-per-view card already co-headlined by bantamweight champion Holly Holm's first defense against Miesha Tate, McGregor elected to fight a late replacement in a non-title bout. He and the UFC settled on Diaz (19-10), the tough-talking, well-rounded veteran from an infamous fighting family.

"The fans show up here every time," McGregor said, the cheers of his boisterous Irish fan base rising from the crowd. "They pay their hard-earned money to travel across (the ocean). People pull out of fights, and then the other opponent just scraps the whole card, only thinking about themselves in their comfortable home while the fans have saved up money and been hyped for an event."

But Diaz, who has fought at lightweight and welterweight, understandably hadn't been preparing and likely couldn't make the 155-pound limit. After negotiations, the fighters agreed to meet at a whopping 170 pounds — 25 pounds more than the limit for McGregor's last bout three months ago.

McGregor already faces a hungry struggle to make 145 pounds, and his coaches have encouraged him to abandon the weight permanently. He won't do it, instead plotting a strategy to hold titles in multiple weight classes.

This generous weight limit means McGregor, who is three inches shorter than Diaz, was able to eat normally during training. With extra pounds of muscle in his core, he expects an accompanying increase in his already impressive punching power.

And though the fighters had only two weeks to promote their bout, the two gifted trash-talkers have already developed a heated dialogue.

Starting with a boisterous news conference in suburban Los Angeles last week, the fighters have creatively criticized nearly every aspect of their opponent's outlook on mixed martial arts, fame and life. They've questioned each other's toughness and accused each other of being dishonest about the genesis of their weight limit agreement.

"As the fight comes closer, he's like a scared little boy," McGregor said. "He's trying to pass the limelight. That's what a man does when he's scared. He shies away and tries to pass it on."

They both specialize in poking at their opponents' foibles, too. McGregor has brought up obscure details of the Diaz brothers' training camps and hard-knocks background stories, while Diaz has laughed at McGregor's unorthodox training methods — including his unusual use of a movement coach, Ido Portal.

Diaz referred to McGregor's much-publicized movement training as "playing touch-butt with that dork in the park with the ponytail. ... You have a guy swinging a pool noodle at you, smacking you in the face with it."

When they posed following Thursday's news conference, Diaz approached McGregor with his fist pointing at McGregor's face. McGregor slapped it away, forcing UFC President Dana White to step between them. Security and Las Vegas police acted quickly to calm down the fighters' camps.

It was just another day in show business for McGregor, who aspires to master every aspect of the fight game.

"I enjoy showing up and giving the fans a show," McGregor said. "And I love to fight."