(This story appears in today’s edition of USA TODAY.)

LAS VEGAS – It’s not hard to get UFC President Dana White excited when talking about the fighters on his roster, but his enthusiasm reaches a different level with Conor McGregor.

“I don’t know if there’s ever been a fighter we’ve ever had that has what this kid has,” White tells USA TODAY Sports and MMAjunkie.

Even UFC Chairman and CEO Lorenzo Fertitta, who generally takes a more measured approach to his discourse, struggles to mask his enthusiasm for the 26-year-old Irish featherweight, who headlines his first televised UFC event this weekend.

“I hate even saying this, but with his gift of gab and his athletic ability and fighting ability, it’s almost like the Irish Muhammad Ali in a way,” Fertitta says. “To compare anybody to Ali is kind of stupid because of all the other great things that were associated with him from a social movement and everything else. But Conor has just got that sparkle, that thing to him.

“Wherever he goes – whether we put him on TV, whether he’s doing an interview, whether he’s around a group of people – he just is the center of attention. He’s got that special quality, and for a guy that’s fought in the UFC four times to have the interest of GQ Magazine, Men’s Health, ESPN? He’s got it.”

Just two years ago, neither White nor Fertitta had even heard of McGregor, a Dublin native who was on his way to a plumbing career before he chose a prizefighting life. But in April 2013, when White was honored by Dublin’s Trinity College, Irish fight fans earned McGregor his call to the sport’s biggest promotion.

“I’m out one night at Temple Bar with a ton of fans, and everybody was saying, ‘Conor McGregor, Conor McGregor, Conor McGregor,'” White says. “I thought he was a heavyweight for some reason, the way everyone was talking about him. So I come back here, and I ask (UFC matchmakers) Joe Silva and Sean Shelby, ‘Who the hell is Conor McGregor? That’s all I hear out there.’ Then I said, ‘Sign him. Sign him. Everybody talks about him there. Sign this kid.’

“Once they started negotiating with him and we were close to getting a deal signed, I flew him out here to Las Vegas, and we went to dinner. Afterward, I called Lorenzo up, and I said, ‘Lorenzo, I don’t know if this kid can fight, but if he can fight just a little bit, this kid is going to be huge.'”

As it turns out, McGregor can certainly fight. In four UFC bouts, he’s picked up three first-round finishes. The one bout that went to a judges’ decision was a hard-fought victory over a gritty Max Holloway, and McGregor actually blew out his ACL early in the fight but continued until the final bell.

“I had never met the kid,” Fertitta recalls. “Conor came up and was apologizing to me for not stopping Max.”

Despite just four UFC appearances, McGregor was the second-most popular athlete on MMAjunkie in 2014. His showmanship and ample fighting skills have proven a perfect mix.

“What he has is unbelievable confidence in himself, and when he sits in a room with you, you start to believe everything he’s saying, too,” White says. “And he has a really good gift of explaining and breaking down a fight and how a fight is going to go and why it’s going to happen. It’s hard to argue with the kid.

“He is also so good at stirring up the hate with the other fighters. He’s so very good at doing that.”

On Sunday McGregor (16-2 MMA, 4-0 UFC) looks to truly establish himself as one of the UFC’s biggest stars as he takes on Dennis Siver (22-9, 11-6) in the headlining bout of “UFC Fight Night 59: McGregor vs. Siver,” which takes place at Boston’s TD Garden and airs on FOX Sports 1 (7 p.m. ET).

The UFC’s marketing efforts for the event have focused almost solely on McGregor, but the strategy seems to have worked. White and Fertitta are expecting a sellout and say 10-12 percent of the tickets were sold to Irish fans who will travel to the U.S. for the fight.

“Mickey Rourke has been blowing me up about this fight,” White says. “Mickey Rourke is coming. Mickey Ward is coming. All the Irish guys are coming out. It’s big.

“When you look at the hubs of Chicago and New York and Philadelphia, the Irish movement with a Conor McGregor can be as big and powerful as the Hispanic movement was with Oscar De La Hoya back in the day. It hasn’t really happened yet, but the Irish population in the U.S. and the U.K. and all over the world is pretty unbelievable.”

If victorious McGregor’s been promised a shot at featherweight champion Jose Aldo, who will be cageside at Sunday’s event. That matchup is one that could potentially fill a stadium in either Aldo’s native Brazil or McGregor’s Ireland, the UFC execs say. McGregor has to take care of Siver first, but if successful, both White and Fertitta believe Aldo vs. McGregor is the biggest fight the UFC can make this year, in any division.

“Conor wins this fight, he could become a household name,” Fertitta says. “He’s going to be that big, and this is the beginning of it. We truly believe it.”

For more on UFC Fight Night 59, check out the UFC Rumors section of the site.