[1] Choi started getting noticed in the MMA world after making his DEEP debut in June 2010, when he faced Yusuke Kagiyama.
After a short stint on the independent circuit, Choi returned to DEEP in September 2010, facing Atsuhiro Tsuboi.
[2] He went undefeated in his next fights in MMA, beating various fighters like Mitsuhiro Ishida, Kosuke Omeda, and Nobuhiro Obiya.
Before being released to fight in the UFC, Choi fought for DEEP one last time, on June 15, 2013, when he faced Japanese prospect Shoji Maruyama.
[5] In November 2013, following a nine-fight winning streak, Choi signed a contract to fight with the UFC to compete in their featherweight division.
[8] Choi ultimately made his debut when he faced Juan Puig on November 22, 2014, at UFC Fight Night 57.
[19] Choi was briefly linked to a bout with Renan Barão which was expected to take place on April 15, 2017, at UFC on Fox 24.
[20] However, as the announcement of the pairing began to circulate, Choi declined the bout, and as a result, Barao is expected to be rescheduled against a different opponent, possibly at another event.
[22] However, Choi pulled out of the fight on June 14 citing an injury and was replaced by promotional newcomer Calvin Kattar.
[31] Returning after a three-year layoff, Choi faced Kyle Nelson on February 4, 2023, at UFC Fight Night 218.