Ssireum (until 2004) At the 2003 Ssireum Championships, he won the title against his long-time rival Kim Young-hyun (often anglicised to Younghyun Kim). A year later, he reached the final again, where he was defeated by Kim. Across all
Combat sport styles, there has never been anywhere a fight of such physical proportions between two athletes. Choi weighed standing tall, Kim weighed standing tall. This even surpasses the
WBA heavyweight championship between
Nikolay Valuev ( at ) and
Jameel McCline ( at ), which is considered a record in
boxing in terms of physique. Valuev and McCline brought together and , Choi and Kim and .
K-1 (2005–2008) He announced in December 2004 to leave Ssireum for
K-1, and stated he has a two dan black belt in
Taekwondo. But this could never be verified. Prepared for his kickboxing career by K-1 fighter
Nicholas Pettas, he debuted in K-1 fighting at the
World GP 2005 event in
Seoul in March, 2005, which he won in the final vs.
Kaoklai Kaennorsing. In the final elimination he defeated
Bob Sapp with a 2–0 decision, eventually losing to
Remy Bonjasky in the World Grand Prix Final. He got his nickname "Techno Goliath" () when he was a
ssireum wrestler in South Korea, as after a victory he would dance to techno music. He is referred to on Japanese television and news articles as the 'Korean Monster' (コリアン・モンスター). He started the season 2006 at the K-1 World GP in
Las Vegas with a unanimous decision win over
Sylvester Terkay aka "The Predator". His new coach was the former Japanese Korean K-1 fighter Kin Taiei (anglicised to
Taiei Kin). One of Choi's most notable fights was against current K-1 World Champion
Semmy Schilt at the World GP 2006 event in Seoul. The fight was unique due to the enormous size and weight of both fighters (Schilt , Choi ). Choi won the fight by 2-0 decision, but it was a disputed win. On September 30, 2006, Choi fought
Jérôme Le Banner in the final eliminations, and lost after three rounds and one extra round on points. After the fight, Le Banner said: ''"He is dangerous, his knees are already almost at the level of my head, he's not human! But he's a good guy and I like him, he's very tough, maybe the strongest guy in K-1, and he has hard bones -- when I kicked him, it hurt my leg! I'm sure with more experience, in two years no one will be able to knock him out!"'' On March 4, 2007, in the World Grand Prix in Yokohama, he was knocked out for the first time in his career.
Mighty Mo landed his trademark overhand right to the chin and Choi was not able to stand up again. In this fight he weighed , was very slow and many say it was his worst performance. On August 5. at the Asia World Grand Prix in Hong Kong, he beat
Gary Goodridge by KO at 1:34 in the first round. the heaviest weight of his K-1 career (2005-2008). In the post-fight Choi said: ''"He (Jérôme) has been my toughest opponent, who was able to resist my powerful punches and counter with speed, I admire his physical strength and I'm sure with more experience will be able to defeat him."'' On September 27 at the K-1 final Elimination in Seoul, he came back to K-1 and fought against the current Heavyweight champion
Badr Hari. After 3 rounds of fighting, Choi's corner threw in the towel due to a rib injury. Although Hari was unable to faze Choi with two heavy punches thrown in the first and second rounds, in the third round he began targeting Choi's ribcage with punches and kicks. Notable: In the years 2008 and 2009, Hari fought 14 bouts and only lost 3 of them, one by disqualification against
Remy Bonjasky, two by KO against
Alistair Overeem and Semmy Schilt. From his 11 wins, he won 8 times by KO in the first round, against
Ray Sefo,
Glaube Feitosa, Domagoj Ostojic,
Frédéric Sinistra, Semmy Schilt,
Zabit Samedov,
Ruslan Karaev and Alistair Overeem. Only
Peter Aerts and
Errol Zimmerman survived the first round, Aerts lost by KO in the second round, Zimmerman in the third round. Choi stated before his bout against Hari:
"He is a great fighter, but I will be different from those who fell in the opening round". Choi was the only from Hari's 11 defeated opponents in 2008 and 2009, who was able to take his best punches and kicks to the head, body and legs without going down once. Hari said after the fight,
"I tried to knock him out in the first round, but he has a really strong chin." Since his last fight, Choi has lost much weight. He was announced with a weight of . Choi was picked as a first reserve fighter against
Ray Sefo at the 2008 K-1 Championship finals which he lost by unanimous decision. The English version of the fight from
HDNet Fights was commentated by
Michael Schiavello and Mike Kogan, Co-Commentator was
Kimbo Slice. Slice stated he saw Choi the day before at
breakfast, and pointed out how big and huge he is. Slice:
"Hongman is a really big guy, he is really tall. Fighting him would be a real challenge to any fighter." In the last 23 seconds of the bout, Sefo landed a very hard overhand right to Choi's jaw, but the Korean took it without any damage. Sefo knocked out many opponents with the same right hand, including Jérôme Le Banner, Gary Goodridge and Ruslan Karaev. Schiavello pointed out how the same punch broke the jaw of Le Banner in four places, and Kogan stated: ''"To Choi's credit, i don't think the people realize the power in Sefo's punches. That landed flush on his jaw, and Choi just shook it off and kept moving forwards, that's ridiculous."''
Mixed martial arts career (2006–2009) K-1 Dynamite On December 31, Choi fought his first
mixed martial arts fight on
K-1 Dynamite, facing former TV star
Bobby Ologun, whom Choi outweighed by a large margin. Choi was scheduled to face former
WWE,
IWGP, and
NCAA national champion amateur
wrestler Brock Lesnar at the combined
promotion event
K-1 Dynamite!! USA, a pay-per-view event at the
Los Angeles Memorial Coliseum, on June 2, 2007. However, reportedly due to a benign tumor on his
pituitary gland, Choi was denied his
California fighter's license on May 23, 2007, putting Dynamite!! USA's main event in jeopardy only 10 days before its scheduled occurrence. Choi was replaced in the fight by fellow Korean fighter
Kim Min-soo. He was confirmed to fight former
Pride heavyweight champion
Fedor Emelianenko at
Yarennoka on
New Year's Eve. Choi opened the fight landing on top of Fedor during a
takedown attempt, after which the Russian attempted an
armbar from the bottom to no avail. The sequence repeated itself, only the second time Fedor showed the difference in experience and locked the armbar, forcing Choi to tap at 1:54. Choi fought again in Dynamite!! 2008, being scheduled to fight
Mirko Cro Cop. The fight was longer, as Cro Cop, a fellow K-1 specialist, found difficult to strike against the larger Choi. He did land multiple
low kicks through the round, which eventually caused enough damage for the fight to be stopped in a KO for Cro Cop.
DREAM Choi's next MMA match would be for the
Dream promotion. He faced retired baseball player
Jose Canseco in an MMA match on May 26, 2009, as part of its Super Hulk Tournament. Choi beat Canseco in 1 minute 17 seconds. The Korean advanced to the semi-finals at
Dream 11 and was pitted against
Ikuhisa Minowa, a Japanese fighter familiar with large differences in size. Minowa resorted to creative takedown and
guard pulls to bring the match to the mat, but Choi used his size and strength to shut down his gameplan. Eventually Minowa pinned Choi in
side control and landed
knee strikes, which the Korean answered to by landing some ground and pound later through Minowa's guard. At the next round, however, Minowa took Choi down and immediately locked a
heel hook, making Choi submit. Choi was expected to participate in
Dream 14, which was supposed to have taken place in
Seoul, South Korea. But many factors, including the issue that many top Korean stars such as
Denis Kang and him (Choi) were not available in April, contributed to the event being canceled.
Military service and inactivity (2008–2015) In April 2008, Choi joined the
Korean army for his 21 months military service. After failing two medical tests, he was relieved from his military duty. The main reason was a problem with the sight in his left eye, which was the result of a
brain tumor. On June 9, the tumor was finally removed through surgery. Choi did not compete in any competitions between October 2009 and July 2015. He frequently appeared in TV shows, game shows, and a few movies during those years. Many critics believe he never reached his best shape after this long break. Even though he was technically very limited and mostly lost to the best K-1 and MMA fighters, his greatest strengths were his very good
chin, overall punch and kick resistance, and a very strong
Muay Thai knee strike. Fighters like Carlos Toyota or David Mihajlov don't have a similar
Knockout-ratio or punching power as
Badr Hari,
Jérôme Le Banner or
Mighty Mo. Only Mo was able to knock him out during Choi's time in K-1 (2005–2008), although the Korean stated he had not trained and was not in shape at that time, and backed up this claim in the rematch by not just appearing in top shape against Mo, but also by taking his best punches. During his best days, Choi was also able to take all punches and kicks from
Bob Sapp,
Semmy Schilt and
Remy Bonjasky without being knocked down or out once. Le Banner had four fights with
Mark Hunt, and he took him down a total of three times, once with hard kicks to the legs, once with a kick to the head, and once with a counter punch to the head, and Hunt received an eight count each time. Hunt is considered one of the most durable fighters in K-1 and MMA, with very good
chin and general punch and kick resistance. But still he was floored by Le Banner three times, and was also
knocked out by a
liver kick from Schilt. Schilt knocked out many of his opponents with punches and kicks, and Le Banner had with over 80% the highest
knockout ratio in the entire
K-1 Circus. Choi took every attack to the head, body, and legs from Le Banner and Schilt, never went to the floor, and was never counted out or received an eight count in his bout with the Dutchman and his two bouts with the Frenchman.
Comeback (2015–present) Road Fighting Championship In July 2015, after 5 years and 9 months of inactivity in combat sport, he gave his comeback against Brazilian fighter Carlos Toyota, weighing , the lowest to this day. He lost via knockout in the first round (multiple punches to face and jaw). Toyota was the second fighter besides Mighty Mo who knocked out Choi with head punches. On December 26, 2015, he competed in the Openweight Tournament "ROAD FC 027" in China. His opponent in the quarterfinals was Chinese Luo Quanchao. Choi was able to win the fight by T.K.O in the first round and advance to the semifinals. In April 2016, he fought the "Chinese" Aorigele, whom he defeated by knockout in round one. He was weighing . On September 24, 2016, Choi, at a new fighting weight of , competed in the finals of the Openweight Tournament. Despite intense preparation against the strong puncher Mighty Mo, who knocked him out with a heavy head punch back in 2007, Choi was not able to avoid another
Knockout defeat by a head punch from Mo.
Kickboxing On November 6, 2016, Choi returned to a kickboxing ring for the first time since December 2008. At the Silk Road Hero Kickboxing event in China, he lost a unanimous points decision to China's Zhou Zhipeng. Choi weighed 160 kg, while Zhou weighed only with a height of On November 27, 2017. At the AFC event in South Korea, he defeated Japan's Noboru Uchida by a unanimous points victory. On November 15, 2018, he fought at the Chinese event MAS FIGHT against
Wushu (sport) Fighter
Yi Long, who weights standing . The fight was scored under strange circumstances as a
Technical knockout win for the Chinese. Yi kicked Choi with a spinning kick below the waist at 1.30 minutes into the first round, after which Choi sat down on the floor with a painfull face, and stayed there for several minutes. The referee was Tony Weeks, known from
Boxing, who, among other famous fights, refereed the World Heavyweight Championship fight between
Wladimir Klitschko and
Tyson Fury in
Düsseldorf in November 2015, when Fury dethroned the long reigning Champion Klitschko. Choi complained to Weeks, that Yi had kicked him to the groin, but Weeks disagreed and judged Choi's behavior as refusing to fight. Various slow-motion footage and photos show that while Yi's kick was not clearly to the groin, but it was below the beltline. On June 11, 2019, he lost to David Mihajlov of
Hungary, who sent him to the ground with several head shots 49 seconds into the first round, and the referee stopped the fight after a brief count. Choi weighed , Mihajlov . Apart from Mighty Mo in 2007 and 2016 and Carlos Toyota in 2015, Mihajlov was the third man to knock Choi out with head shots.
Professional Wrestling On July 21, 2019 Choi gave a shot at professional wrestling when he worked for
Dragon Gate's Kobe Pro Wrestling event. His only match was a victory over
Ryo Saito and
Stalker Ichikawa in a handicap match. ==Outside the ring==