Early life & beginning of Muay Thai career

Jongsomboon Yangsapyot was born as Somboon Yangsapyot in Rayong province as the 6th child in a family of 10. He started his Muay Thai training at the age of 9 under Kru Chan Fungfueng in the Leutawan-ok gym. He fought around 20 times in his neighborhood under the ring name of "Samingnoom Leutawan-ok" until he became well-known in the area. His success caught the attention of former yodmuay Wichit Praianan who was also the #1 Muay Thai trainer in eastern Thailand at the time. Praianan brought him to the popular Praianan/Lukbangplasoi camp co-owned by Ukrit Tansavad^[1] with the goal of honing his ability until he became a yodmuay (elite fighter) himself. Under the new ring name of "Singdam Or.Ukrit," he would make his Bangkok debut by defeating the KO artist Yokthai Sit.Or who is the camp senior of the highly skilled Nong-O Gaiyanghadao and Petchtanong Petchfergus.^[2] He would later change his legal name to Jongsomboon Yangsapyot.^[3]

Singdam was later qualified to begin fighting at the prestigious Lumpinee Stadium and won 17 fights in a row, defeating other up-and-coming fighters such as "The Teep-to-the-Face Man" Rotnarong Daopadriew and Takrawlek Dejrath.

Elite career in Bangkok

On 1992 Singdam was matched up against one of the most significant Muay Femur fighters of the Muay Thai golden era Saenklai Sit Kru Od, drawing against him and then defeating him in the rematch. In the same year he would beat Yodkhunpon Sittraiphum and Duangsompong Por.Pongsawang, 2 fighters who were renowned for their high durability and powerful striking.

Singdam fought his way through the top fighters under 120 lbs with his powerful, fast, and consistent left kick which earned him the nickname of "The World-Ending Left Kicker" by the Thai media. His kicking style meant that Singdam was a Muay Tae fighter (fighter who primarily kicks). Singdam's style is unusual since most Muay Tae fighters are rope-a-dope Muay Femur fighters but Singdam preferred to be a aggressive pressure fighter.^[3] His second signature technique was his left punch which was combined well with his southpaw kicking style, giving him another way to pressure forward as well as to set up his left kick.

1993 was the peak of Singdam's career, during this time he would be up against the fighters who resided at the ceiling of the bantamweight division (118 lbs). Veeraphol Sahaprom, Samson Isaan, Silapathai Jockygym, and especially "The Two-Time Fighter of the Year" Kaensak Sor.Ploenjit all lost to him in within the year. In Singdam's matchup against Kaensak, he was knocked down by a right hook and then less than 20 seconds later he knocked down Kaensak with a left hook and landed a right hook as he fell. Although Kaensak was also doing well for the rest of the fight, Singdam would outscore the highly respected fighter with his left kick as well as with various techniques to try to nullify and counter Kaensak's explosive Muay Femur style.^[4] Singdam won the bout and both fighters earned the 1993 Fight of the Year award. His victory against Kaensak was the fight that he was most proud of; in addition Singdam was paid 250,000 baht which was the highest purse of his career.^[2] In comparison, the usual purse of elite fighters was 100,000 baht^[5] and it was rare for one to receive a purse of 200,000 baht and above.^[6]

From 1991 to 1996, Singdam was considered to be the greatest bantamweight fighter in the Kingdom of Thailand even if he was not able to secure a title. Singdam was famed for his rivalries against Saenklai Sit Kru Od and Anantasak Panythaphum. Singdam was qualified to compete for the bantamweight championship twice against Saenklai but was denied both times even if Singdam would win by a large margin against him in their other fights. In 1994, Singdam was winning by a large margin against Dara-ek Sitkrungsap but the referee announced Dara-ek as the winner. The audiences rioted, going so far as to climb the metal fence that separated the VIP area from the rest of the stadium. Singdam's corner as well as military officers climbed into the ring. Instead of giving the win to Singdam, the officials declared the fight a no contest.^[7] Singdam would still continue beating yodmuay afterward, defeating the technical Jaowehar Looktabfah multiple times as well as Manopchai Singmanasak.

Retirement & later years

Later on in his career, Singdam had to move up to junior featherweight (122 lbs), then eventually to featherweight (126 lbs), and his performance as a Muay Thai fighter began declining. Singdam is considered an unlucky yodmuay in Thailand as every time he fought for a title, he would be denied by his opponent despite being highly successful in his other matchups. After losing to underdog Anantachai Monsongkhram in 2003, Singdam retired from Muay Thai, reasoning that he grew disinterested with weight cutting. Singdam's victories against Kaensak Sor.Ploenjit and Veeraphol Sahaprom were considered his best fights. He was matched up against another powerful southpaw kicker, Padejsuek Kiatsamran, but they did not fight.^[3] Singdam cites the Muay Maat fighter Chatchainoi Chaorai-Oi as the opponent who hurt him the most in a fight.^[2]

After his fighting career, Singdam married a woman from Chonburi and now has 2 daughters. He went to Japan to work as a Muay Thai trainer before returning to Thailand to become a municipal employee and opened a seafood stand on a market.^[8] As of 2022, he is working as a hired hand and gardener.^[2]