Reinier De Ridder Bio
Reinier De Ridder, born on September 7, 1990, is a Dutch professional mixed martial artist who currently competes in the middleweight division of the Ultimate Fighting Championship (UFC). He is widely recognized by his ring name, The Dutch Knight, and by his initials, RdR. Standing 6 feet 4 inches tall with a reach of 79 inches, he is regarded as one of the most accomplished grapplers to enter the modern middleweight ranks. Beyond competition, De Ridder owns and operates a physical therapy clinic in his adopted hometown of Breda, Netherlands.
Before joining the UFC, De Ridder built his reputation in ONE Championship, where he became a former ONE Middleweight World Champion and ONE Light Heavyweight World Champion. He was the third fighter in company history to hold two division titles at the same time. As of October 21, 2025, he is ranked number 8 in the UFC middleweight rankings, a position that reflects both his recent surge and his long-standing grappling pedigree.
Early Life and Background
Reinier de Ridder was born on September 7, 1990, in Tilburg, Netherlands. He began training in Judo at the age of six, an early introduction to combat sports that shaped the technical foundation of his fighting style. Years of consistent training earned him a black belt in Judo while he was still in his teens, marking him as a serious martial artist from a young age.
After finishing high school, De Ridder enrolled in college and expanded his grappling base by adding Brazilian Jiu-Jitsu to his skill set. His dedication on the mats paid off when he was awarded a black belt in Brazilian Jiu-Jitsu, an achievement that set the stage for his future in mixed martial arts. Outside of training, De Ridder established a professional career in physical therapy and continues to run a clinic in Breda, where he balances the demands of competition with patient care.
Path to MMA
De Ridder’s competitive grappling résumé includes a silver medal at the European Jiu-Jitsu Championship in 2016, where he competed in the 94.3 kg purple belt division. That result on the international stage helped confirm that his skills could translate beyond the academy and into a professional fighting career. He also returned to submission grappling at high-profile events, including a draw with multiple-time ADCC champion André Galvão at ONE X in March 2022 and a decision loss to Tye Ruotolo at ONE Fight Night 10 in May 2023.
De Ridder made his amateur mixed martial arts debut in 2013, winning by first-round submission, before turning professional later that same year with another first-round triangle choke victory. He strung together seven straight wins, all ending in stoppages, and captured the HIT FC Middleweight Championship with a first-round rear-naked choke. The performance drew offers from both the UFC and ONE FC, and De Ridder chose ONE due to what he described as better contractual terms.
Reinier De Ridder Career
Early Career (2013-2018)
During his first five years in professional mixed martial arts, Reinier de Ridder built a reputation as a finisher. His seven-fight opening streak featured a series of submissions and strikes that left no room for the judges, and his HIT FC Middleweight Championship win cemented his status as a top regional prospect in Europe. He continued to sharpen his game at Combat Brothers, the gym that remains his training home.
Operating primarily out of the middleweight and cruiserweight divisions during this period, De Ridder stayed active on the European circuit while balancing his college studies and his physical therapy work. His early results convinced promoters abroad that he was ready for a bigger stage, and by late 2018, offers from major Asian and American organizations had begun to arrive.
ONE Championship Breakthrough (2019-2024)
De Ridder made his ONE Championship debut at ONE: Hero’s Ascent on January 25, 2019, submitting Fan Rong in the opening round. He followed that performance with a second-round knockout of Gilberto Galvao at ONE: Legendary Quest and a hard-fought decision win over former title contender Leandro Ataides at ONE: Warrior’s Code. Those three victories positioned him for the biggest fight of his career.
On October 30, 2020, at ONE: Inside the Matrix, De Ridder challenged Aung La Nsang for the ONE Middleweight World Championship and won by first-round submission. Less than six months later, on April 28, 2021, at ONE on TNT 4, he stepped in on short notice to face Aung La Nsang again, this time for the ONE Light Heavyweight World Championship, and won by unanimous decision. The double victory made him the third simultaneous two-division champion in ONE history.
De Ridder continued to defend his middleweight title, stopping Kiamrian Abbasov via arm-triangle choke at ONE: Full Circle in February 2022 and submitting former champion Vitaly Bigdash with an inverted triangle choke at ONE 159 in July 2022, with both performances earning him Performance of the Night bonuses. His reign ended on December 3, 2022, at ONE on Prime Video 5, when Anatoly Malykhin knocked him out in the first round of their light heavyweight title fight. A middleweight title rematch with Malykhin at ONE 166 on March 1, 2024, ended in a third-round technical knockout loss.
UFC Era (2024-Present)
After parting ways with ONE Championship, De Ridder stopped Magomedmurad Khasaev by first-round TKO at UAE Warriors 51 on July 27, 2024, and signed with the UFC on September 24, 2024. He opened his UFC tenure with an arm-triangle choke submission of Gerald Meerschaert at UFC Fight Night 247 on November 9, 2024, then submitted Kevin Holland by rear naked choke in the first round at UFC 311 on January 18, 2025.
On May 3, 2025, at UFC on ESPN 67, De Ridder handed three-time NCAA Division I wrestling champion Bo Nickal his first mixed martial arts loss, finishing the bout with a second-round technical knockout via a knee to the body that earned him his first UFC Performance of the Night award. He followed that with a split decision win over former UFC middleweight champion Robert Whittaker in the main event of UFC on ABC 9 on July 26, 2025, a result that nine of sixteen media outlets scored in his favor.
Style and Strengths
De Ridder is a grappling-first fighter whose black belts in Judo and Brazilian Jiu-Jitsu give him a clear edge once the fight hits the mat. He favors arm-triangle chokes, rear naked chokes, and inverted triangle submissions, often chaining positions until his opponents are forced to tap. His long frame and 79-inch reach allow him to control opponents from top position, while his judo background helps him dictate where exchanges take place.
Notable Events and Milestones
Becoming the third simultaneous two-division champion in ONE Championship history ranks as his most significant career milestone. His knockout of Bo Nickal stands as a defining UFC moment, while the split decision win over Robert Whittaker established him as a legitimate contender in the middleweight division. He also owns a European Jiu-Jitsu Championship silver medal from 2016, a result that helped launch his combat sports career.
Reinier De Ridder Career Wins
Reinier de Ridder has compiled a professional mixed martial arts record of 21 wins against 4 losses, with the majority of his victories coming by submission. He has stopped opponents with chokes, joint locks, and ground-and-pound strikes across multiple promotions and weight classes.
ONE Championship Highlights
De Ridder captured the ONE Middleweight World Championship by submitting Aung La Nsang in October 2020 and added the ONE Light Heavyweight World Championship with a unanimous decision over the same opponent in April 2021. He defended the middleweight strap twice, against Kiamrian Abbasov and Vitaly Bigdash, both by submission. His reign also included knockout and submission wins over Fan Rong, Gilberto Galvao, and Leandro Ataides.
Other Wins and Performances
Outside of ONE, De Ridder’s early professional run included the HIT FC Middleweight Championship and a seven-fight finishing streak between 2013 and 2018. He also scored a first-round TKO of Magomedmurad Khasaev at UAE Warriors 51 in July 2024, a result that served as his final appearance before joining the UFC roster.
Reinier De Ridder Family
Family Background and Racing Lineage
Reinier de Ridder’s documented family background is limited in public sources, and no details about his parents or siblings have been confirmed for publication. He is of Dutch nationality and grew up in Tilburg before relocating to Breda, where he currently resides.
Personal Life
De Ridder lives in Breda, Netherlands, where he owns and operates a physical therapy clinic alongside his training and competition schedule. He is known by the ring name The Dutch Knight, a nickname that reflects both his nationality and his disciplined, classical martial arts background. Publicly available information about a spouse or children has not been confirmed.
2025 Season Performance
Reinier de Ridder’s 2025 campaign transformed him from a promising newcomer into a top-ten middleweight contender. He opened the year with a first-round rear naked choke submission of Kevin Holland at UFC 311 in January, then stunned the division by finishing Bo Nickal with a second-round technical knockout in May, an outcome that earned him the UFC Performance of the Night award.
The biggest statement of his year came on July 26, 2025, when he outpointed former champion Robert Whittaker by split decision in the main event of UFC on ABC 9, a result that pushed him into the number 8 spot in the official UFC middleweight rankings by October 21, 2025. However, his momentum stalled on October 18, 2025, at UFC Fight Night 262, when he was stopped by Brendan Allen via fourth-round technical knockout after Anthony Hernandez withdrew from the originally scheduled main event due to injury.
Despite that late setback, De Ridder’s 2025 record confirmed his place among the division’s elite grapplers and set up a strong platform for the following year. Operating out of Combat Brothers and continuing to balance his physical therapy clinic with competition, he remains a serious threat to any middleweight contender heading into the next calendar year.
