Fifa has contacted the Thailand government over the case of Bahraini footballer Hakeem Al-Araibi.
The 25-year-old, who holds refugee status in Australia, is being held in a Bangkok prison on an Interpol warrant issued by Bahrain.
He was sentenced in Bahrain for vandalism but denies the charges.
In a letter to Thai Prime Minister Prayut Chan-o-cha, Fifa says the former Bahrain player is "at serious risk of mistreatment in his home country".
The footballer fled to Australia in 2014. He was granted political asylum in 2017 and plays for Melbourne football club Pascoe Vale.
In 2014, he was sentenced in absentia in Bahrain to 10 years in prison for vandalising a police station.
He was on a holiday in Thailand when authorities detained him at a Bangkok airport on 27 November.
He fears he will be tortured and possibly killed if he is extradited back to his home country and in an interview with the Guardian newspaper, said the ongoing case had left him "terrified" and "losing hope".
Fifa general secretary Fatma Samoura has contacted the prime minister seeking a speedy resolution to the case.