Former Buriram United coach Masatada Ishii will take charge of the Thai national men's football side, replacing German-Brazilian tactician Mano Polking, team manager Nualphan Lamsam confirmed on Wednesday.
The decision to end Polking's two-year reign through "mutual consent" came after Thailand's 3-1 victory at Singapore in a 2026 World Cup qualifier on Tuesday night.
Nualphan, affectionately known as "Madam Pang," said in a social media post that both Polking and the Football Association of Thailand (FAT) had been informed of the development.
She also confirmed that Ishii, 56, will become the second Japanese coach of the War Elephants with immediate effect.
His compatriot Akira Nishino was in charge of the Thai team for two years from 2019–2021.
Thailand are currently second behind leaders South Korea in Group C in the second round of Asian qualifiers for the 2026 World Cup, to be co-hosted by Canada, Mexico and the United States.
After two games, South Korea have six points, Thailand and China three each, and Singapore zero.
The Thais began their campaign with a 2-1 home loss to China which led to a large number of fans calling for Polking's ouster.
"No one can ignore the results of our two World Cup qualifying games so far," said Nualphan.
"Everyone, including myself and the players, had high expectations but what has happened is difficult to stomach, especially the 2-1 loss to China in our first game last week.
"I have already informed the FAT president [Somyot Poompunmuang] because I think it's time for a change.
"After a discussion with Mano, we have agreed to part by mutual consent. I thank him for his dedication and hard work -- at least he helped us win the Asean title twice."
Ishii's first match as coach of Thailand will be against his own country on Jan 1, 2024 when the War Elephants take on Japan in a friendly at Tokyo's National Stadium.
Ishii guided Kashima Antlers to the J-League and Emperor's Cup titles in the 2016 season.
After his mid-season dismissal from Kashima in 2017, Ishii served as head coach of Omiya before his stints at Thai clubs Samut Prakan City and Buriram United.
Ishii steered Buriram to three titles last season.
He was appointed technical chief of the Thailand team for the King's Cup in Chiang Mai in September.
He quit the post and returned to Japan after the tournament.
A few weeks ago, Ishii told a Thai website that he left the country because Thai officials failed to honour their promise to appoint him as Thailand coach.
It was reported that Polking cried after the victory at Singapore National Stadium on Tuesday.
Earlier, Suphanat Muenta scored twice for the War Elephants in the 66th and 87th minutes after Supachok Sarachat gave the visitors the lead after just five minutes.
Shawal Anuar was on target for the Lions in the 41st minute.
Although Thailand dominated for long periods, their strike force looked out of sorts until Polking sent on veteran forward Teerasil Dangda, who has just returned from an injury, in the second half.
The 35-year-old forward made his presence felt with two assists for Suphanat.
In the other Group C game on Tuesday, Son Heung-Min scored a brace and set up the other as South Korea made it two victories from two with a 3-0 win in China.
The third round of matches will take place on March 21, 2024 when Thailand visit South Korea and Singapore host China.