Derek Cruz looks to have another promising youngster in his care with Joy And Fun, who turned the opening event at Sha Tin on Sunday into a one-horse race. Joy And Fun was having only his second start but belied that relative inexperience with a very professional display under a typically competent Olivier Doleuze ride. Joy And Fun was always well placed but quickened up impressively when Doleuze pressed the button some 300 metres out. He went to the line merely under a hand ride from the Frenchman, whose horsemanship has ensured the well will not be dry when Joy And Fun fronts up again next start. Cruz is a very good trainer and, in fact, a very underrated one. It was great to see him rewarded with a career-best win last season with Natural Blitz in the Cathay Pacific Hong Kong Sprint, and Green Treasure went within an ace of knocking off world champion Vengeance Of Rain in the 2005 Hong Kong Cup Trial. In the minds of many observers, it was cruel to see owners take horses like Fruity Fruity, Green Treasure and Greenessy off him, to be transferred to other trainers, after he had achieved so much with them. This season, Cruz has overseen the development of Sir Ernesto from Class Two also-ran to a Panasonic Cup winner, and he was again in the thick of the action on Sunday with Natural Blitz, who was placed third to Able Prince in the Hong Kong Sprint Trial. Joy And Fun is by Cullen, a young stallion that may not be familiar to many Hong Kong racing fans. Cullen is a younger brother to the successful sire Danasinga (sire of Danacourt), though he was probably a bit more precocious than that horse, having won the Group Three Blue Diamond Preview over 1,000m as a two-year-old. He also ran fourth in the Group One Blue Diamond Stakes. Cullen's other Group One credential came at three years old, when he was a close second to Cannsea in the Railway Handicap at Ellerslie in Auckland, New Zealand. Cullen is a son of Danehill, from the grand producing mare Princess Tracey, a Group Three winning sprinter in Ireland in her racing days. Princess Tracey has been a goldmine at stud, with her progeny including Group One winners Tracy's Element (champion filly and mare in South Africa), Danasinga (Group One Stradbroke Hcp), Group Two-winning South African filly Topsannah and Group Three-winning sprinter Towkay, who gained his most important win as a sire on Sunday when Armada won the Group Two Cathay Pacific International Mile Trial.