Making the announcement on Thursday evening, the Football Association of Thailand said that the Japanese tactician's contract was terminated after the national team did not meet the goals set by the association for the qualifying tournament where Thailand finished fourth in their group behind United Arab Emirates, Vietnam, and Malaysia.
The country's preparations for the 2022 AFC U-23 Championship qualifiers, 2021 AFF Suzuki Cup and 2023 AFC Asian Cup qualifiers third round will now be handled by technical director Carles Romagosa, a former Barcelona youth coach, as the association begins the search for a new head coach.
Nishino, who previously led Japan to the 2018 World Cup Round of 16, was handed the reins of of the Southeast Asian nation in July 2019 as the replacement for Milovan Rajevac, who was fired following Changsuek's poor showing in the AFC Asian Cup earlier that year.
Thailand's World Cup qualification campaign under Nishino got off to a decent start with wins against Indonesia and UAE in 2019. However, they missed out on a place in the next stage after failing to record a win in the tournament as it resumed this year following the coronavirus disruptions.
Vietnam were the only ASEAN side to progress from the second round of the qualifiers after finishing one point behind UAE in Group G.
Also assigned the responsibility of the Thai Under-23s, Nishino led the host nation of the 2020 AFC U-23 Championship through a group that also featured Australia, Iraq and Bahrain before losing 1-0 to Saudi Arabia in the quarter-finals.