[6] Chiasson started mixed martial arts at the age of 19, after being bed-ridden for three and one-half weeks recovering from a car accident to get back the fitness level she once was when she was a softball player in high school.
[12] In the semi-finals, Chiasson faced Leah Letson[13] She once again finished the bout by way of knockout in round one.
[15][16] She won the fight via a rear-naked choke submission in round two and winning the Ultimate Fighter women's featherweight tournament.
[19] On February 10, 2019, Chiasson replaced an injured Leah Letson and faced Sarah Moras on May 4, 2019, at UFC Fight Night: Iaquinta vs.
[27] Chiasson was scheduled to face Sijara Eubanks on September 5, 2020, at UFC Fight Night 176.
[28] However, Chiasson pulled out of the fight for undisclosed medical reasons and was replaced by Karol Rosa.
[29] The bout between Chiasson and Marion Reneau was originally scheduled for UFC Fight Night: Overeem vs.
[33] Chiasson was scheduled to face Aspen Ladd on July 24, 2021, at UFC on ESPN: Sandhagen vs.
[37] Chiasson replaced Julia Avila to face Raquel Pennington on December 18, 2021, at UFC Fight Night 199.
[47] Chiasson faced Pannie Kianzad in a rematch on March 16, 2024, at UFC Fight Night 239.
[51] She won the fight by technical knockout via doctor stoppage after landing an elbow which opened a cut above Silva's eye.
[53] Chiasson was re-scheduled to face Ketlen Vieira on February 22, 2025 at UFC Fight Night 252.