Initially competing in the all-striking ONE Super Series, Stamp made her mixed martial arts (MMA) debut on October 11, 2018.

Stamp started practicing Muay Thai at the age of 5 in order to avoid bullying in school, with her father training her.

Stamp has won a gold medal at the 2019 Siam Cup BJJ tournament in the women's gi 58.5 kg class.

[9] Stamp lost the title to Todd via a closely contested split decision, marking her first-ever loss in ONE Championship.

[10] Stamp Fairtex was then scheduled to defend her Atomweight Muay Thai belt for the second time during ONE Championship: A New Breed on August 28, 2020, with her opponent being the Queens of the Ring Flyweight Tournament winner Allycia Rodrigues.

[12] On January 11, 2023, it was announced that Stamp would face Anissa Meksen for the interim ONE Women's Atomweight Kickboxing World Championship.

[14] After being scouted by Rich Franklin, Stamp made her mixed martial arts debut on ONE Warrior Series 2 on July 19, 2018.

[15] In 2019, Stamp announced her intentions to continue to compete in mixed martial arts in ONE Championship, with the goal of becoming a ONE World Champion in MMA as well.

[22] Leading up to her fight with Tomar, Stamp voiced interest in facing Mei Yamaguchi, who she said possessed high-class wrestling skills, to test her own level.

[28] Despite dominating the majority of the fight, Stamp lost by submission via a last-effort guillotine choke in the closing seconds, earning her first loss in MMA competition.

[30][31] Stamp faced Alyona Rassohyna in a rematch as the quarterfinal bout of ONE Women's Atomweight Grand Prix at ONE Championship: Empower on May 28, 2021.

[35] Stamp was scheduled to face Seo Hee Ham in the semi-final bout of ONE Women's Atomweight Grand Prix at ONE Championship: NextGen on October 29, 2021.

[38] Stamp faced Ritu Phogat in the ONE Women's Atomweight Grand Prix Final at ONE: Winter Warriors on December 3, 2021.

[39][40] She defeated Phogat by submission via armbar in the second round to win the 2021 ONE Women's Atomweight World Grand Prix Championship.

Fairtex holds a total Muay Thai record of 64 Wins, 17 Losses, 5 Draws; only a select number of these fights are listed in the table