One of Australia's most controversial jockeys, Danny Nikolic, has been barred from all Victorian racecourses by the state's new chief police commissioner Graham Ashton, reports The Age newspaper.

Nikolic, a former champion apprentice and a winner of major races across Australia, including the 2003 Caulfield Cup on Mummify,was recently informed by police of the ban. It is understood he will fight the ruling.

Nikolic, who is serving a suspension from Racing Victoria and is applying for a riding licence in Queensland, has had a colourful career that includes heated clashes with the state's leading racing integrity officer, Terry Bailey.

Police sources have confirmed the decision to ban Nikolic from Victorian racetracks. It follows a 2012 decision by Ashton's predecessor, Ken Lay, to bar the jockey from Crown Casino.

Lay's 2012 decision was the first time police had used their casino-exclusion powers since the height of Melbourne's underworld war in 2006.

The decision to ban the jockey from the casino created a stir in racing circles, where success often leads to a big night at the venue. A leading owner said: "It would have been interesting if we'd won a major race and I wanted to take him back to Crown for a celebratory night."

The casino ban and racetrack ban are partly based on information uncovered by detectives in 2011, which sparked a major race-fixing inquiry known as the "Smoking Aces affair".

Detectives had secretly intercepted phone calls of Nikolic and his brother, John, and uncovered information that suggested the pair were involved in an alleged conspiracy to fix a race, which Smoking Aces won at Cranbourne in April, 2011.

Nikolic was riding Smoking Aces in the race and another jockey, Mark Zahra, later privately conceded that he had been offered $3000 by Nikolic to ride his mount in a way that favoured the run of Smoking Aces.

Betting records showed relatives of Nikolic placing large bets on Smoking Aces.

However, Victoria's Office of Public Prosecutions told police there was insufficient evidence to charge Nikolic or any other person.

The law has now been changed in Victoria to make it easier for detectives to charge sporting figures with cheating or race fixing.

But racing stewards have never been able to utilise the evidence from the phone calls tapped by police, due to the strict limitations on the way such evidence can been shared by police, making it almost impossible for the evidence to be used in sporting disciplinary proceedings.

Police are also still investigating the 2011 shooting murder of Nikolic's father-in-law, horse trainer Les Samba. It was reported this week that detectives are investigating a Melbourne-based suspected drug dealer, who is also a high-level punter and former associate of underworld boss, Tony Mokbel, and a Bandidos bikie associate in connection to Samba's slaying.

The Herald Sun reported that police have CCTV footage of a person of interest buying a phone card from a newsagent, which was later used to make phone calls to Samba shortly before he was shot dead on Beaconsfield Parade, Middle Park.

Fairfax Media is not suggesting Nikolic was involved in the death of Samba.