Nikolic, 38, who appeared in the Victorian Civil and Administrative Tribunal on Tuesday in a bid to overturn a two-year ban from racing, is accused of assaulting another jockey, Mark Pegus, his girlfriend, Rikki-Lee Hull, and a police officer in three separate incidents last year.

A two-day committal hearing on the charges was due to start today in the Melbourne Magistrates Court but was postponed until next year.

Prosecutor Senior Constable Nathan Sinclair said the case was ready to go but had been delayed until May because of witness availability.

Magistrate Ian McGrane agreed to adjourn the case for a two-day hearing from May 30 but sought assurances from Nikolic's defence lawyer, barrister Sandy Robertson, there would be no further delays.

Mr Robertson said he would notify the court co-ordinator before the case was due to begin if there were any problems. Nikolic was not in court today.

At the previous hearing in April, Mr Robertson said the jockey admitted being at Caulfield racetrack and St Kilda's Barkly Hotel where the alleged assaults took place but denied assaulting Mr Pegus or Ms Hull.

Nikolic faced a total of six charges including using a telecommunication device to menace a person at Caulfield on January 17 last year.

He was charged with one count of recklessly causing injury, one count of assault, and two counts of intentionally causing injury to Mr Pegus at the Caulfield racetrack stables on January 18 last year.

He was also charged with assaulting Ms Hull, Mr Pegus' girlfriend, at the Barkly Hotel on March 7 last year and assaulting police officer Julio Salerno when being questioned at St Kilda police station on April 6.

Five police officers and seven civilians will be called to give evidence at the hearing.

Nikolic was banned from racing for two years for threatening chief steward Terry Bailey and his family in September. His appeal against his ban concluded in VCAT on Tuesday with Judge Michael Macnamara reserving his decision.