It is advisable to take a good look at the fifth trial held at Sha Tin down the straight course on Tuesday where several potential winners competed, including Ricky Yiu Poon-fai's Great Idea. This son of Group One July Cup winner Anabaa has been working in an impressive style for some time and confirmed that promise when leading virtually all the way. Robbie Fradd had a double-handful as he went across the wire and following a thorough preparation, Great Idea looks destined to prove competitive when he makes his debut. Yiu must also have taken immense pleasure in witnessing Top Health finishing within a head of the winner under Eddie Lai. The New Zealand-bred son of Deputy Governor was asked for more of an effort this time round, following a quiet turf trial last month, but has progressed in leaps and bounds since then and clearly has an engine. Eddie Lo Kwok-chow's Star Of Shantou has been working in a solid manner for some time and with Douglas Whyte sticking to him like glue for the majority of his trackwork, there is plenty to suggest he is one to follow when he first steps out. In the same trial, Shanghai Friend, who competes today, also caught the eye under an extremely quiet ride from Glyn Schofield. Interestingly, Schofield had previously been aboard Top Health in an impressive trial and, having opted to ride this fellow, the alarm bells began ringing. Caspar Fownes' classy galloper The Duke hit the line with a good deal of zest, and looks in outstanding condition. The third heat was held over the Sha Tin mile, where the best effort came from Derek Cruz's Good Fit. This fellow has trimmed down significantly since his only outing this term, which clearly served as a fitness enhancer. Now the quality of work has picked up Good Fit can be expected to run well when he next appears. Potential Hong Kong sprint representatives Silent Witness and Firebolt finished in that order in the fourth heat, which, at 58.1 seconds, was the fastest of the morning. It was almost unbelievable how easily Silent Witness could travel when clocking this sort of time and it was enough to frighten any future adversary. Even so, Gary Ng Ting-keung's Tsz Wan Fortune (rated 72) was more than worth a second look based on his effort in finishing third. He displayed good early speed and although pressured in the concluding stages showed signs of potential. Given his current mark, he looks one to follow. Danny Shum's California Prince is a long way from being the finished article, and while fitness will improve drastically following his work there are some positives to come out of his trial. David Hayes' lightly raced Sunday Delight was arguably the one to take from the sixth heat. Under Jimmy Quinn, he made steady ground all the way to the wire and looks a good deal fitter for one run this season. He is still on the learning curve but shows enough improvement to warrant close attention the next time he is running. There is little doubt Triumph has picked up the quality of his work and that was underlined by his effort when winning the seventh trial. In his two starts this season he has failed to deliver on the promise he'd shown as a griffin, but he has raced himself into form and must be kept safe next time. The same applies to Supersonic, who displayed a good deal more zest with the blinkers applied. He was given a testing ride by Whyte and responded well enough inside in the final 200 metres. Ones To Note: Top Health, Tsz Wan Fortune, Sunday Delight.