First-season trainer Tony Cruz, who has had a sensational start to his new career, is the central figure in an inquiry into a prohibited substance found in his stable. Jockey Club veterinarians removed the substance late on Tuesday, and it was then sent for analysis. An inquiry was opened last night but was then adjourned until Saturday. The substance has not been named, but reliable reports suggest it was an anti-bacterial ointment on the long list of substances prohibited for use on horses in training - or that it contained substances on the banned list. Nine horses from the Cruz stable which ran at Happy Valley last night were all tested following the discovery, but all were clear and permitted to race. Cruz has had a momentous first year as a trainer, with the highlight to date a superb victory by Deauville in the Hong Kong Gold Cup. Cruz and Jockey Club officials offered no comment last night. Meanwhile, next season will start with a new trophy race to reflect the handover on July 1. The Governor's Cup, usually a mid-season race run off at Happy Valley, has slipped into history. In its place will be the SAR Chief Executive's Cup, and this will be the feature race on the first day of the new season, replacing the traditional Kwangtung Handicap Cup, which has held pride of place for at least three decades. It is expected that Tung Chee-hwa, as chief executive, will attend at Sha Tin to present the trophy. He is not a noted racegoer, having been more closely associated with football in earlier years.