Sor Rungvisai knows from experience the challenge awaiting new boxer McGregor against Mayweather

As Conor McGregor attempts to convert from a mixed martial arts champion to a boxer capable of defeating the unbeaten former five-division world champion Floyd Mayweather Jr., one man in Thailand offers some unsolicited perspective.

“It’s going to be difficult for McGregor. It’s two different sports, and it takes time to adjust,” Srisaket Sor Rungvisai told the Los Angeles Times through an interpreter recently in a telephone call from his training camp.

Sor Rungvisai, 30, claimed a significant boxing upset of his own this year by knocking down then-unbeaten four-division world-champion Roman “Chocolatito” Gonzalez in the first round of their March 18 World Boxing Council super-flyweight title bout at Madison Square Garden and proceeding to a victory by decision.

That completed a dedicated transformation for Sor Rungvisai, whose rematch with Gonzalez is the Sept. 9 main event of an HBO-televised super-flyweight tripleheader at StubHub Center.

From the age of 13 to 16, Sor Rungvisai was a Muay Thai fighter, competing against foes in a stand-up style similar to the form McGregor has thrived in with the UFC, including the use of kicks, elbows and knees permitted in addition to boxing.

Muay Thai fights are routinely staged throughout Southern California, but the pay is a fraction of what UFC fighters and pro boxers earn, and that’s why Sor Rungvisai was prodded by his girlfriend and her family to scrap the native fighting style for an opportunity at better pay in Japan.

“The adjustment from Muay Thai to boxing was hard,” Sor Rungvisai said. “And McGregor has to adjust to the point that he has to match Floyd Mayweather’s boxing skill.”

What are the most difficult aspects of the transition?

“Many things,” Sor Rungvisai said. “It’s totally different. In Muay Thai, you can use kicks and elbows. When I started to fight in boxing, everything was different, including how you throw punches and how I stood.

“In my first [boxing] fight, I had to constantly tell myself not to kick the guy. It took many years to get that thought out of my mind fully … around two full years to get used to boxing, then a few more years to become a world-class boxer.”

McGregor, who became the UFC’s first simultaneous two-division champion when he repeatedly knocked down then-lightweight champion Eddie Alvarez en route to a second-round technical knockout victory in November, took off extra time awaiting the birth of his first child in May before the Mayweather deal was finalized and his training sharpened.

McGregor meets Mayweather (49-0) Aug. 26 at T-Mobile Arena in Las Vegas in a $100 Showtime pay-per-view bout in which few other than MMA die-hards and conspiracy theorists are giving him a real chance to win.

“It’s going to be very difficult, and I believe McGregor will have to control himself very hard not to use the kicks or other moves,” Sor Rungvisai said. “When you get in the ring, you have the muscle memory to do what you’re used to.”

Any slip like that could draw a disqualification, and Mayweather’s team has also mentioned legal action if McGregor, 29, inflicts any injury on the boxing champion by delivering any banned punishment reserved for the UFC octagon.

Although McGregor is believed guaranteed to pocket somewhere around $100 million for the fight, pride is an incentive for the confident Irishman who has vowed to finish Mayweather “inside four rounds.”

Sor Rungvisai felt that motivation after starting 1-3-1 as a pro boxer, with other record-keeping listing him at 9-6-1, before he fought a pivotal 2010 bout in Thailand.

“I decided I didn’t want to get hurt by boxing anymore and said to myself that if I lost that one more time, I’d not do it again,” he said. “I got motivated. I aligned with my current team and was trained properly. And from that date, I won 17 straight fights and won the WBC belt for the first time in 2013.”

He lost that belt a year later to Sept. 9 undercard fighter Carlos Cuadras of Mexico, but has reeled off 16 consecutive victories since and is confident about his chances in the Gonzalez rematch.

“I definitely think I won [the first fight]. I threw a lot of punches, and when you look at it by round, I won,” Sor Rungvisai said.

“I’ll make it a great fight. I’m focused on making the fans happy in watching me fight, particularly the fans from Thailand. I want to make them proud. I want to show the world a boxer from Thailand can be one of the best in the world on a very great stage like the one in the U.S.”

In his own way, he’s already shown McGregor anything in boxing is possible.

lance.pugmire@latimes.com

@latimespugmire