TV Globo reporter Eric Faria got the threats following Santos' elimination by Flamengo in the Copa do Brasil quarter-final on Wednesday.
The game at the Vila Belmiro ground ended 4-2 to Santos but Flamengo went through on away goals, with one of the key moments coming shortly before halftime when Santos were awarded a penalty just yards from where Faria was positioned.
The referee changed his mind after consulting with the linesman and the fourth official, who, Santos said, was warned to review the decision by Faria, even though Video Assistant Referees (VAR) were not being used.
In a letter to the Brazilian Football Confederation, Santos accused Faria of behaving more like a fan than a reporter and appealed for the result to be annulled.
The club, famous as home to Pele and Neymar, said Faria had past history in interfering in games from the sidelines and called for a blanket ban on pitch-side reporters.
"Football is going crazy," a shaken Faria told the Redacao SporTV programme on Friday morning. "I am here today talking about a flimsy, false accusation that is giving me headaches on social media. I’ve received a load of death threats, people telling me that if I go to the Vila Belmiro I’ll leave in a hearse, that I am going to get beat up, stoned, and all that."
Brazilian football has experienced several controversies in recent years involving pitch-side reporters and officials with access to TV replays. Before VAR, referees were not allowed to look at replays but some clubs have long suspected the rule was flouted.
(Reporting by Andrew Downie; Editing by Christian Radnedge)