[5][6] After graduating from high school Cirkunov found Brazilian jiu-jitsu, briefly relocating to Las Vegas to train but returned to Canada to open his own gym.

[5] In 2008, Cirkunov won the black belt super heavy division at the Pan No-Gi Jiu-Jitsu Championship.

[5] Cirkunov made his professional debut in January 2010 and amassed a record of 9–2 before signing a four-fight contract with the Ultimate Fighting Championship in the summer of 2015.

[8][6] Cirkunov was expected to make his promotional debut against Sean O'Connell on August 23, 2015, at UFC Fight Night 74.

[10] Cirkunov defeated Jolly via first-round KO after achieving full mount and battering him when he turned his back.

[11] Cirkunov faced promotional newcomer Alex Nicholson on February 6, 2016, at UFC Fight Night 82.

"[14] Cirkunov next faced another promotional newcomer in Ion Cuțelaba on June 18, 2016, at UFC Fight Night 89.

[22] However, the pairing was delayed after a recent hand surgery for Teixeira was slow to heal and the bout eventually took place on December 16, 2017, at UFC on Fox 26.

[37] Cirkunov faced Krzysztof Jotko in a middleweight bout on October 2, 2021, at UFC Fight Night 193.

[43] After two straight losses at Middleweight, Misha was scheduled to return to Light heavyweight against Shamil Gamzatov on August 6, 2022, at UFC on ESPN: Santos vs.