Demetrious Johnson to face Muay Thai standout Rodtang Dec. 5 in mixed-rules bout in Singapore

ONE Championship has put together an incredibly interesting styles clash for what is being described as the promotion's biggest show ever.

Former UFC flyweight champion Demetrious Johnson will fight Muay Thai standout Rodtang in a "mixed special rules fight" at ONE X, the ONE Championship 10-year anniversary show Dec. 5 in Singapore, CEO Chatri Sityodtong announced Wednesday on "The MMA Hour." Sityodtong described ONE X as the "biggest, most unique show in the history of the company."

Johnson and Rodtang will be contracted at 135 pounds for a four, three-minute round affair. The first and third rounds will take place under Muay Thai rules. The second and fourth rounds will be fought under ONE mixed martial arts rules.

"We've never done crossover stuff [before] like the old-school days of Asian MMA," Sityodtong said.

Johnson, 35, is one of the best fighters in MMA history, compiling a 30-4-1 record. "Mighty Mouse" held the UFC flyweight title from 2012 to 2018, a historic run. Johnson, a Washington state resident, holds the record for most consecutive title defenses in UFC history (11).

Rodtang, 24, is the reigning ONE 135-pound Muay Thai champion, known for his durability and charisma. The Thailand native had more than 250 wins in Muay Thai. His first fight came at the age of 8.

Also on the ONE X card, per Sitoyodtong, Bibiano Fernandes will defend his 145-pound ONE title against all-action UFC veteran John Lineker, and Brazilian jiu-jitsu star Garry Tonon will meet Thanh Le for the 155-pound belt.