Navid Afkari, a 27-year-old athlete from Shiraz, Iran was charged with murder after authorities claimed he stabbed a water utility worker to death.
The wrestler was slapped with two death sentences.
Critics argue that he and his two brothers, who have also been arrested, were tortured during their interrogations.
They claim they were framed due to their alleged attendance at 2018 nationwide
demonstrations over the government's poor handling of the economy.
Iran does not always announce the execution dates for the condemned, sparking fears that Afkari could be quietly put to death out of the public eye.
"We really are at one minute to midnight," Brendan Schwab, executive director of the World Players Association, which represents 85,000 professional athletes told
The New York Times.Schwab added that Afkari was specifically targeted because of his high-profile as an athlete.
"He participated in a widely attended protest and has been targeted in many ways because of his profile as an athlete," Schwab added.
"People really need to stand up," said Rob Koehler, the director general of Global Athlete, a lobbying group for athletes.
The group has previously been involved in clemency trials.
Tortured confessionEarlier this week, Iran broadcast Afkari’s televised admission to the murder in a segment that, to many, appeared nothing short of a coerced confession.
It followed a number of worrying signs about Afkari's case in a country where trials and punishments are often dealt with by authorities behind closed doors.
"The last that I heard from Navid's mother was that all communication had been cut off," said Sally Roberts, a former Olympic wrestler. "He has been moved to an undisclosed area."
"They tortured my sons to confess against Navid," said Bahieh Namjoo, their mother.
"There was one sham trial. My children could not defend themselves."
She added: "I am asking for help from anyone hearing my voice."
Afkari's case has drawn the attention of the international sporting community, sparking an online campaign that includes a video statement from Dana White, president of the mixed martial arts Ultimate Fighting Championship.
"He went to a peaceful protest in Iran and he's going to be executed for that," White said in a video on Friday. "He's one of us. He could be any of my fighters."
Iran put to death 251 people last year, more than any country but China, according to Amnesty International.
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