Seika Izawa

Mixed martial arts career Izawa began training mixed martial arts in June 2020 due to the COVID-19 pandemic preventing her from competing in judo.

Jewels (2020–present) Early success Izawa made her professional debut against Mika Arai at Deep Jewels 30 on October 31, 2020. She won the fight by unanimous decision.

Izawa was scheduled to face the interim Jewels Strawweight champion Miki Motono in a non-title bout at Deep Jewels 32 on December 19, 2020. She won the fight by unanimous decision, with scores of 30–27, 30-27 and 29–28.

Strawweight Champion Izawa and Miki Motono fought a rematch for the interim Jewels Strawweight Championship at Deep Jewels 33 on June 19, 2021. She won the fight by a first-round submission, forcing Motono to tap with an armbar at the 3:32 minute mark. It was the first stoppage victory of her professional career. Izawa was promoted to undisputed champion on March 15, 2022, after Mizuki Inoue vacated the belt.

Izawa made her atomweight debut against Si Woo Park at DEEP 104 Impact on October 23, 2021. She won the fight by unanimous decision, with scores of 28–27, 29-26 and 29–26. Park was deducted two points in the second round for an illegal soccer kick. Following this victory, Fight Matrix recognized Izawa as the fifth best atomweight in the world.

Rizin FF (2021–present) Super Atomweight Champion Izawa faced the reigning Rizin Super Atomweight champion Ayaka Hamasaki in a non-title match at Rizin 33 - Saitama on December 31, 2021. She won the fight by technical knockout, stopping Hamasaki with a mixture of grounded elbows and punches. It was the first knockout victory of her professional career. After beating Hamasaki, Izawa was ranked as the best atomweight in the world by both Fight Matrix and Sherdog.

Izawa challenged the reigning Rizin Super Atomweight champion Ayaka Hamasaki at Rizin 35 on April 16, 2022. She was once again able to utilize her superior grappling to win the fight by unanimous decision.

Super Atomweight Grand Prix At a press conference held by Rizin on July 7, 2022, it was announced that Izawa would participate in an eight-women grand prix, with a ¥7,000,000 prize for the eventual tournament winner. Izawa faced the undefeated Laura Fontoura in the tournament quarterfinals, which were held at Rizin 37 - Saitama on July 31, 2022. She won the fight by a first-round submission, forcing Fontoura to tap with a guillotine choke at the 3:47 minute mark of the opening round.

Izawa was expected to face Rena Kubota in the tournament semifinals, at Rizin 38 on September 25, 2022. Kubota was forced to withdraw from the bout however, as the orbital bone fracture which she sustained in her previous fight hadn't yet healed. Kubota was replaced by Anastasiya Svetkivska. Izawa won the fight by a second-round submission, as she forced her opponent to tap to an armbar with just four seconds left in the round.

Izawa rematched Si Woo Park in the final of the Rizin Super Atomweight Grand Prix on December 31, 2022, at Rizin 40 She won the Grand Prix and the bout in a close bout via split decision.

Continued title reign Izawa was expected to face the one-time Rizin Super Atomweight title challenger Miyuu Yamamoto in a non-title bout at Rizin 42 on May 6, 2023. The fight was postponed for New Year's Eve, as Yamamoto tore her anterior cruciate ligament in training and was forced to undergo surgery.

Izawa faced Suwanan Boonsorn in a women's super atomweight bout at Deep Jewels 41 on May 28, 2023. She won the fight by unanimous decision.

Izawa made her first Rizin Super Atomweight title defense against Claire Lopez at Super Rizin 2: Rizin X Bellator on July 30, 2023. She won the fight via ninja choke submission in the first round.

The match between Izawa and Miyuu Yamamoto in a non-title bout was rescheduled on December 31, 2023, at Rizin 45. She won the fight via rear-naked choke submission in the second round.

Izawa challenged Si Yoon Park for the Jewels Atomweight championship at Deep Jewels 44 on March 24, 2024. She won the fight via ninja choke submission in the second round.

Izawa faced Kanna Asakura in a non-title bout at Rizin 48 on September 29, 2024. She won the fight by unanimous decision.

Izawa faced Lucia Apdelgarim in a non-title bout at Rizin 49 on December 31, 2024. She won the fight via armbar submission in the first round.

Izawa formally vacated her Jewels Strawweight Championship on July 11, 2025.

Izawa faced Shin Yu-jin at Super Rizin 4 on July 27, 2025. Shin failed to make weight at the official weigh-ins, as she came in .5 lbs over the strawweight limit. Izawa won the fight by a first-round arm-triangle choke submission.

Izawa made her second Rizin Super Atomweight title defense against Saori Oshima at Rizin Landmark 12 on November 3, 2025. She won the bout via unanimous decision.

Izawa made her third Rizin Super Atomweight title defense against Rena Kubota at Rizin: Shiwasu no Cho Tsuwamono Matsuri on December 31, 2025. She won the fight by a second-round submission.

On April 12, 2026, at Rizin Landmark 13, Izawa announced she vacated the super atomweight title as she is pregnant.

Championships and accomplishments Grappling Japan Wrestling Federation 2012 Junior Queen's Cup Runner-up (-52 kg) 2012 All Japan Junior High School Championship Winner (-57 kg) Women's Sumo Association 2019 All Japan Women's Sumo Championship Ultra-Lightweight 2nd Place (< 50 kg)

Mixed martial arts Jewels Jewels Strawweight Championship (One time; former) Jewels Atomweight championship (One time; current) Rizin FF Rizin FF Women's Super Atomweight Championship (One time; former) Three successful title defenses 2022 Rizin Women's Super Atomweight Grand Prix Champion eFight 2x "Fighter of the Month" (April 2022, March 2024) Fight Matrix 2022 Female Fighter of the Year Women's Atomweight Lineal Championship (One time; current) MMA Fighting 2022 Third Team MMA All-Star 2023 First Team MMA All-Star 2024 Second Team MMA All-Star 2025 First Team MMA All-Star Uncrowned 2025 #5 Ranked Women's Fighter of the Year

Mixed martial arts record Win

Rena Kubota Submission (guillotine choke) Rizin: Shiwasu no Cho Tsuwamono Matsuri

Saitama, Japan Win

Saori Oshima Decision (unanimous) Rizin Landmark 12

Kobe, Japan Win

Shin Yu-jin Submission (arm-triangle choke) Super Rizin 4

Saitama, Japan Win

Lucia Apdelgarim Submission (triangle armbar) Rizin 49

Saitama, Japan Win

Kanna Asakura Decision (unanimous) Rizin 48

Saitama, Japan Win

Park Si-yoon Submission (ninja choke) Deep Jewels 44

Tokyo, Japan Win

Miyuu Yamamoto Submission (rear-naked choke) Rizin 45

Saitama, Japan Win

Claire Lopez Submission (ninja choke) Super Rizin 2

Saitama, Japan Win

Suwanan Boonsorn Submission (triangle choke) Deep Jewels 41

Tokyo, Japan Win

Park Si-woo Decision (split) Rizin 40

Saitama, Japan Win

Anastasiya Svetkivska Submission (armbar) Rizin 38

Saitama, Japan Win

Laura Fontoura Submission (guillotine choke) Rizin 37

Saitama, Japan Win

Ayaka Hamasaki Decision (unanimous) Rizin 35

Chōfu, Japan Win

Ayaka Hamasaki TKO (elbows and punches) Rizin 33

Saitama, Japan Win

Park Si-woo Decision (unanimous) DEEP 104 Impact

Tokyo, Japan Win

Miki Motono Submission (armbar) Deep Jewels 33

Tokyo, Japan Win

Miki Motono Decision (unanimous) Deep Jewels 32

Tokyo, Japan Win

Mika Arai Decision (unanimous) Deep Jewels 30

Tokyo, Japan

Jiu-jitsu record