Trainer Paul Beshara will fight to clear his name after being found guilty of illegally injecting Happy Trails on the morning the horse was due to race in last month's Dato Tan Chin Nam Stakes.

Beshara's evidence was described as "fanciful" by Russell Lewis, the head of Victoria's Racing Appeals and Disciplinary (RAD) Board, when he handed down the verdict on Friday.

The RAD Board will hear submissions on penalty on Monday with Beshara looking at a mandatory six-month ban unless there is a finding of special circumstances.

"I'll go all the way," Beshara said.

"Basically they are saying we are liars."

Happy Trails, the last-start winner of the Group One Turnbull Stakes, is scheduled to race next in the Cox Plate at Moonee Valley on Saturday week.

Lewis said the board accepted the evidence of Racing Victoria's Compliance Assurance Team (CAT) stewards who raided the stables where Adelaide horse Happy Trails was housed on the morning of the Moonee Valley race.

CAT member Dion Villella said he inspected the near-side jugular of Happy Trails at 9am on race morning and found no abnormalities.

Villella and fellow CAT member Kane Ashby returned almost two hours later, shortly after Beshara arrived at the stable, and discovered a damp area on the horse's neck.

Another inspection about five minutes later revealed a raised area had formed consistent with a haematoma and when Villella applied fingertip pressure, blood oozed from that area.

Lewis said Beshara's explanation the wet patch could have been sweat or water was rejected and labelled the trainer's explanation the horse could have laid down in urine as "fanciful".

"In the end the Board is of the opinion that Beshara's explanation for the damp area and the oozing of blood amounts to sheer invention," Lewis said.

Happy Trails had been treated for a skin condition in the days leading up to the race.

No syringe or equipment was found but Judge Lewis said Beshara had "ample time" in the six minutes before stewards arrived to inject the horse and hide any instruments in the stable complex.

The RAD Board also accepted Racing Victoria's chief veterinarian Dr Brian Stewart's opinion that the swelling over the jugular vein was the "result of a very recent puncture of the jugular vein by a hypodermic needle".