Yutthana Kaensa (, born 7 January 1998), also known as Stamp Kiatniwat (à ¹Âà ¸ªà ¸Âà ¸¡à ¸Âà ¹ à ¹Âà ¸Âà ¸µà ¸¢à ¸£à ¸Âà ¸´à ¸Âà ¸´à ¸§à ¸±à ¸Âà ¸Âà ¹Â), Stamp Sithmorseng (à ¹Âà ¸ªà ¸Âà ¸¡à ¸Âà ¹ à ¸¨à ¸´à ¸©à ¸¢à ¹Âà ¸«à ¸¡à ¸Âà ¹Âà ¸ªà ¹Âà ¸Â), or Stamp Kratingdaenggym (à ¹Âà ¸ªà ¸Âà ¸¡à ¸Âà ¹ à ¸Âà ¸£à ¸°à ¸Âà ¸´à ¸Âà ¹Âà ¸Âà ¸Âà ¸¢à ¸´à ¸¡), is a professional Thai boxer in the Flyweight division. At the age of 17, he was considered the youngest Thai world champion, although the title was for an interim championship. He is also a former WBA Asia Flyweight champion.
Yutthana Kaensa, nicknamed Stamp, was born in Lao Suea Kok District (then part of Mueang Ubon Ratchathani District), Ubon Ratchathani Province, and is a cousin of Poonsawat Kratingdaenggym, a former WBA Super Bantamweight world champion.
He won the WPBF Light Flyweight title by defeating fellow Thai boxer Kwanthai Sithmorseng, a former WBA Minimumweight world champion, on August 8, 2014, at Sanam Luang, Bangkok. On September 23 of the same year, he captured the WBA Asia Flyweight title by defeating Samuel Tehuayo, an Indonesian boxer, at Ayutthaya City Park, Ayutthaya Province. He successfully defended this title twice.
On July 29, 2015, he claimed the WBA Flyweight interim title by defeating Gregorio Lebron, a Dominican contender, in Loei Province. He later defended the title against Lebron again on February 9, 2016, at Bangkokthonburi University, Bangkok.
On December 31, 2016, he challenged Kazuto Ioka, the reigning Japanese WBA Flyweight world champion, in an elimination bout at Shimazu Arena, Kyoto, Japan. He lost by TKO in the seventh round.
Stamp regularly trained at the boxing gym inside Bangkokthonburi University with Anant Tualue, the former trainer of Chana Porpaoin (a two-time WBA Minimumweight world champion) and Denkaosan Kaovichit, who held both the WBA Flyweight world title and the WBA Super Flyweight interim title.
On May 18, 2018, Kiatniwat lost the WBA Asia Flyweight title after being defeated by TKO in the second round by Jaysever Abcede, a Filipino contender, at Bangkokthonburi University. After the bout, his manager Niwat "Che-Mae" Laosuwanwat stated he would no longer support Kiatniwat's path to a championship, citing concerns that his body was too fragile.