Banned jockey Danny Nikolic is appealing the two-year sanction handed down to him by the Racing Appeals and Disciplinary Board (RADB).
Nikolic earned the ban - which prohibits him from participating in any racing activities, including riding trackwork and attending race meets - for abusing chief steward Terry Bailey at a midweek meeting at Seymour racecourse last month.
The 37-year-old is appealing the suspension at the Victorian Civil and Administrative Tribunal.
The under-fire hoop was alleged to have threatened Bailey by stating: "We've all got families, and we know where yours live."
Bailey was also alleged to have told Nikolic: "I told you I was going to f--- your career."
Nikolic has had ongoing issues with racing officials, being banned four times previously for his behaviour towards stewards.
The current ban could effectively end Nikolic's career in the saddle, with an appeal date yet to be arranged.