It's difficult for any athlete to win a ONE World Title, but it's even more challenging to claim a second golden belt – either in another weight class or a different sport.
Still, a handful of elite competitors have managed to achieve this rare feat.
One of them is reigning two-division ONE world champion Reinier de Ridder, who owns both the middleweight and light heavyweight MMA crowns. Next, he'll defend the ONE middleweight world title against former divisional king Vitaly Bigdash in the main event of ONE 159 on Friday, July 22.
That evening, Janet Todd could also become the next member of the exclusive double-gold club. The reigning atomweight kickboxing queen will square off against Spanish star Lara Fernandez for the ONE interim atomweight muay Thai world title in the co-main event.
Before the action goes down at ONE 159, take a look at every fighter who's held two World Titles in ONE Championship at the same time.
The first person to achieve this historic feat was Martin Nguyen.
In August 2017, "The Situ-Asian" challenged seemingly invincible ONE featherweight world champion Marat Gafurov in a rematch for the belt.
Despite dealing with some early adversity, he overcame the undefeated Dagestani's grappling prowess and knocked him out with an overhand right in the second round.
Then in his very next bout three months later, Nguyen challenged ONE lightweight world champion Eduard Folayang for the gold in front of the defending king's compatriots in Manila, Philippines.
By the second round, "The Situ-Asian" had figured out the Filipino icon's movements, and when Folayang went for a spinning kick, the featherweight titleholder put him to sleep with a picture-perfect overhand right to the jaw.
Just like that, the first two-division ONE world champion was crowned.
Aung La N Sang
Nguyen's close friend, Aung La N Sang, would become the next man to earn champ-champ status in ONE Championship.
After falling to ONE middleweight world champion Vitaly Bigdash in January 2017, "The Burmese Python" rematched him for the gold on home soil in Yangon, Myanmar, just five months later.
The two battled in another competitive five-round affair, but N Sang did just enough to dethrone the mighty Russian and become his country's first world champion in any sport.
In February 2018, the Myanmar superstar made his compatriots proud once again. This time, he dropped Alexandre Machado with a thunderous head kick and unloaded a slew of punches to earn the TKO victory in 56 seconds flat.
With that lightning-quick finish, N Sang added the vacant ONE light heavyweight world title to his collection and officially became a two-division king.
Stamp Fairtex became the first woman to hold two ONE world titles, but unlike the first two competitors on this list, it happened in different sports.
In October 2018, the Thai superstar made her promotional debut against ONE atomweight kickboxing world champion Chuang Kai Ting in front of her hometown fans in Bangkok.
While Chuang tried to use her speed to get into range and unleash her boxing, the Fairtex product overpowered her with kicks, knees, and short punches. That performance earned Stamp the unanimous decision victory and the world title belt.
Still, the rising superstar wasn't satisfied. In her next matchup four months later, Stamp faced debuting American striker Janet Todd for the inaugural ONE atomweight muay Thai world title.
This showdown came under the Fairtex athlete's favored rule set, and it showed. She was able to utilize her full muay Thai arsenal and took home the unanimous decision victory to become a two-sport queen.
After losing the ONE flyweight muay Thai world title in May 2019, the legendary Sam-A Gaiyanghadao moved down to his natural weight class and kicked off his charge toward strawweight gold.
The Thai icon defeated Darren Rolland that October and then switched sports to challenge "Golden Boy" Wang Junguang for the inaugural ONE strawweight kickboxing world title two months later.
Wang maintained a high pace and often put the veteran on the back foot, but Sam-A countered with left punches and his trademark roundhouse kicks to narrowly win the crown via unanimous decision.
That may have been a close battle, but when Sam-A returned to his favored muay Thai rule set and faced Rocky Ogden for the inaugural ONE strawweight muay Thai world title in February 2020, he was much more decisive.
The southpaw's defense was near-flawless, his technique was textbook, and his strikes landed with authority as he cruised to another unanimous decision – and a second belt.
Reinier de Ridder
Reinier de Ridder is the latest member to join this exclusive champ-champ club.
"The Dutch Knight" originally challenged two-division king Aung La N Sang for the ONE Middleweight World Title in October 2020, and to the shock of many, he put the Myanmar icon down early and submitted him via rear-naked choke in the first round.
Six months later, the undefeated European stepped up on six days' notice to challenge "The Burmese Python" for his light heavyweight belt. It was a different weight class and a different fight, but a similar outcome was achieved.
De Ridder used his world-class grappling to dominate N Sang throughout the five-round affair, ultimately winning via unanimous decision to take the ONE light heavyweight world title.
This story first published at ONEFC.com.