Alonzo Menifield Bio
Alonzo Theodoro Menifield, widely known by the ring name “Atomic,” is an American mixed martial artist competing in the Light Heavyweight division of the Ultimate Fighting Championship (UFC). Born on October 18, 1987, in Los Angeles, California, Menifield turned professional in 2015 and has also competed under the Bellator and Legacy Fighting Alliance banners. As of late November 2025, he holds the #15 position in the UFC light heavyweight rankings. He is recognized for his powerful striking combined with effective grappling skills.
Early Life and Background
Alonzo Theodoro Menifield was born in Los Angeles, California, and grew up facing significant hardship from a young age. After the death of his father, his mother raised him and his brother until the age of 14, when both boys entered the foster care system. Menifield moved through approximately 12 different foster homes during his teenage years, an experience that helped build the resilience that has defined his athletic career.
Menifield attended Canyon High School for two years, where he graduated and excelled at football. He continued his football career at NJCAA Glendale Community College in California, starring primarily as a linebacker and earning Honorable Mention All-American honors in his sophomore year. He was also a member of the track and field team during his time at Glendale. After his first two seasons, Menifield earned a scholarship to Texas A&M University–Commerce, where he graduated with a degree in Criminal Justice. He later played professional football in both the Canadian Football League (CFL) and the Arena Football League.
Path to MMA
Following his professional football career, Menifield transitioned to mixed martial arts and made his professional debut at heavyweight against Zach Rosol on November 20, 2015, at Bellator 146, winning via TKO in the first round. He then dropped to light heavyweight and won his next two fights via TKO and KO, building an early reputation for finishing power. His performances earned him a shot at Dana White’s Contender Series, the UFC’s well-known proving ground for unsigned talent.
Menifield faced UFC veteran Daniel Jolly on July 25, 2017, at Dana White’s Contender Series 3, winning via TKO at the end of round one due to an eye injury, though he did not initially secure a UFC contract. He was given a second chance on June 16, 2018, at Dana White’s Contender Series 9, where he faced Dashawn Boatwright. Menifield won via TKO with ground-and-pound strikes within the first eight seconds of the first round, and this time was awarded a UFC contract.
Alonzo Menifield Career
Early Career (2015–2018)
Menifield began his professional career at heavyweight under the Bellator banner, capturing a first-round TKO victory in his debut. He relocated to the light heavyweight class and continued to finish opponents, recording back-to-back knockout victories that drew attention from major promotions. His progression through regional shows and into Dana White’s Contender Series laid the foundation for his eventual move to the UFC roster.
UFC Debut and Early Promotional Years (2019–2021)
Menifield made his UFC debut on January 19, 2019, against Vinicius Moreira at UFC Fight Night 143, winning via TKO with punches in the opening round. He followed that with a first-round KO win over Paul Craig at UFC on ESPN 3 in June 2019, quickly establishing himself as a finisher inside the Octagon. His first major setback came against Devin Clark at UFC 250 in June 2020, where he lost by unanimous decision, and he later dropped a second-round knockout to Ovince Saint Preux at UFC Fight Night 176 in September 2020.
COVID-19 disruptions impacted his 2021 schedule after a positive test postponed his bout with William Knight. He returned at UFC 260 and submitted promotional newcomer Fabio Cherant via Von Flue choke in round one, then outpointed Ed Herman by unanimous decision at UFC 265. However, his rematch with William Knight at UFC on ESPN 31 ended in a unanimous decision loss, closing out a turbulent but active stretch inside the promotion.
UFC Middle Years (2022–2023)
Menifield bounced back in 2022, stopping Askar Mozharov via technical knockout in round one at UFC Fight Night 207 after original opponent Nicolae Negumereanu withdrew, and then knocking out Misha Cirkunov in round one at UFC Fight Night 212. In early 2023, he faced Jimmy Crute at UFC 284, where a third-round point deduction for grabbing the fence led to a majority draw.
The rematch with Jimmy Crute came at UFC 290 on July 8, 2023, and Menifield earned a decisive victory, submitting Crute via guillotine choke in round two. He capped the year with a unanimous decision win over Dustin Jacoby at UFC 296 in December 2023, strengthening his standing in a competitive light heavyweight field.
Fortis MMA Era (2024–Present)
Menifield trains out of Fortis MMA in Dallas, Texas, and continued to face top-tier competition in 2024. He stepped in as a replacement for Dominick Reyes to face Carlos Ulberg at UFC on ESPN 56 on May 11, 2024, and was knocked out just 12 seconds into round one. He followed that with a second-round knockout loss to Azamat Murzakanov at UFC on ABC 7 in August 2024, putting him in a difficult stretch.
In 2025, Menifield rebounded by defeating promotional newcomer Julius Walker via split decision at UFC Fight Night 252 on February 22, 2025, a performance that earned him a Fight of the Night award. He then won his rescheduled bout with Oumar Sy by unanimous decision at UFC on ESPN 69 on June 14, 2025. Most recently, he faced Volkan Oezdemir at UFC Fight Night 265 on November 22, 2025, and lost by knockout in round one.
Notable Events and Milestones
Among Menifield’s signature moments is his eight-second TKO of Dashawn Boatwright on Dana White’s Contender Series 9, the finish that earned him his UFC contract. His second-round guillotine choke win over Jimmy Crute at UFC 290 stands as one of his most dramatic career victories, while his 12-second knockout loss to Carlos Ulberg represents one of the swiftest setbacks of his UFC run. His 2025 Fight of the Night performance against Julius Walker underscored his reputation for delivering competitive, action-packed bouts.
Alonzo Menifield Career Wins
Across his professional career, Alonzo Theodoro Menifield has compiled a verified record of 17 wins against 6 losses in 24 total professional mixed martial arts bouts. His finishing ability has been a defining trait, with 4 wins by knockout, 3 by submission, and 2 by decision, plus 1 disqualification victory.
UFC Highlights
Menifield’s UFC tenure has featured several memorable finishes and decisions. His first UFC victory came via first-round TKO over Vinicius Moreira at UFC Fight Night 143, and he added a first-round KO of Paul Craig at UFC on ESPN 3 shortly after. Inside the Octagon, he has also recorded a Von Flue choke submission of Fabio Cherant, a TKO win over Askar Mozharov, a knockout of Misha Cirkunov, a guillotine choke victory over Jimmy Crute, a decision over Ed Herman, a decision over Dustin Jacoby, and a split decision over Julius Walker that earned a Fight of the Night bonus.
Other Wins & Performances
Outside the UFC, Menifield posted a first-round TKO in his Bellator debut and added two additional knockout wins before joining Dana White’s Contender Series. His Contender Series performances, including the eight-second finish of Dashawn Boatwright, paved the way for his UFC signing.
Alonzo Menifield Family
Personal Life
Alonzo Theodoro Menifield is married and resides in Dallas, Texas. He and his wife have two sons, Alonzo Jr. and Zavier. After a childhood marked by foster care, he has built a stable family life in Texas while continuing his professional fighting career out of Fortis MMA.
2025 Season Performance
Alonzo Theodoro Menifield’s 2025 campaign inside the UFC Light Heavyweight division has reflected both his durability and finishing instincts. He opened the year by stepping in on short notice to face Julius Walker at UFC Fight Night 252, winning by split decision and earning a Fight of the Night award for his performance. The win helped re-establish his momentum after back-to-back knockout losses in 2024.
Menifield then finally faced Oumar Sy at UFC on ESPN 69 on June 14, 2025, and earned a clean unanimous decision victory, demonstrating growth in his cardio and game planning across a full three rounds. That result moved him back into the UFC’s official light heavyweight rankings, where he was slotted at #15 by late November 2025.
His year closed with a first-round knockout loss to Volkan Oezdemir at UFC Fight Night 265 on November 22, 2025, a setback that prevented late-season upward movement. Despite the loss, his overall 2025 record and ranking position underscore his continued relevance in a stacked light heavyweight field, and he remains a contender capable of breaking into the division’s top tier.