Mark Riley has been convicted and fined $5000 by the Racing Appeals and Disciplinary Board over a positive swab returned by one of his horses.

Riley pleaded guilty to a charge of taking Grand Gallop to the races at Sandown last year with the prohibited substance meloxicam in its system.

Grand Gallop was first past the post in the Sportius Global Events Handicap on December 10 and was subsequently disqualified as the winner of the race.

Riley is training on a stay of proceedings as he seeks leave to appeal his three-year disqualification to the Supreme Court of Victoria.

The trainer was banned by the RAD Board in February over an elevated bi-carb reading returned by Gold For Kev at Sandown in July last year.