Lorenzo Fertitta, chairman and chief executive officer of Ultimate Fighting Championship (UFC).  [Photo provided to China Daily]

In the space of 15 years, two brothers from Las Vegas have transformed UFC from a little known, somewhat frowned upon brand into the dominant company in mixed martial arts.

So much so that it is even competing with more traditional sports.

April 14 will go down as a historic date in the young life of the Ultimate Fighting Championship.

That was the day New York became the last US state to legalize professional MMA fights.

Lorenzo Fertitta, a stocky, well-dressed man of 48 who is the co-owner of UFC, says this is perhaps the last big piece of the puzzle he has been assembling.

"I think it means a lot, because historically, anybody who was a detractor, who was against the sport, first thing they were putting up was, 'well, you're not even legal in New York,'" he tells AFP.

"So obviously, it takes that argument away."

Coming from the casino world, Fertitta and his brother Frank paid a measly $2 million in 2001 for a contest that was known for little more than how violent it was.

Around the same time, the mixed martial arts world developed unified rules that got rid of dangerous fighting moves and set the stage for a new, more respectable image.

But it would be another four years before things really changed with the reality show The Ultimate Fighter, in which UFC hopefuls took each other on.

"The Ultimate Fighter drove casual viewers to watch MMA and the UFC that were never really interested before," says Joe Favorito, a sports marketing specialist.

"They became very quickly educated so they then had a product on free television in the US and in Canada that drove towards their pay per view," he adds.

UFC president Dana White says UFC 196, an event held in March in Las Vegas and featuring Irish superstar Conor McGregor, broke all revenue records for the firm and was watched on TV by 1.5 million paying viewers.

Fertitta said in late December that the company would post revenue of 600 million dollars in 2015.