John Size unleashed four of his seemingly inexhaustible production line of progressive gallopers in Friday's three dirt trials at Sha Tin, headlined by unbeaten star Glorious Days and highlighted by a sparkling effort by unraced three-year-old Can Do. Can Do is a New Zealand-bred colt who hadn't shown much in his first four trials, but first time trialling on the all-weather track he made marked improvement, winning his 1,200m heat by 21/2 lengths in the fastest time of the morning by far (1.11.1). Can Do wasn't asked to do much in his first four go arounds at the trials, as he was allowed to loaf at the back. Last time at Happy Valley he showed some dash, albeit being a bit wayward for Mark du Plessis, but this time he was certainly switched on. With Douglas Whyte on stablemate Earl Of Leitrim, Du Plessis again took the reins and speared to the front on the chestnut. He was challenged in the straight by 106-rated Penglai Xianzi, who always trials well on this surface, but burst away at the furlong pole with an impressively lengthening stride. Penglai Xianzi held on for second and closing off for third was Earl Of Leitrim, another Size charge, who was a solid fourth on debut last month. The four-year-old had won two from three in England and got back and stormed home behind upset winner Windicator Power at Sha Tin over 1,200m. Whyte again had the gelding settled near the tail on Friday and he unwound nicely. The star of the show was Glorious Days, who many are already rating among the best in town after his four-win procession through the grades. His last-start win was probably the least impressive of his efforts, at least in terms of margin of victory, as he ground his way to a short-head Class One win. Whyte reported the gelding was spinning his wheels on a rain-affected track that day, and there were whispers of slight setbacks, but this time the four-year-old was back showing his brilliant best. After being allowed to find his feet at the start and sitting worst than midfield, Whyte began to work into the trial with 400m to go, but still spotted the leaders at least three lengths at the 300m. That's when he clicked up a gear and caught them in what seemed like a flash, accelerated again just past the 200m and travelled beautifully to the line under a firm hold. Sitting half-a-length to his inside, catching the slipstream, was Richard Gibson's Tai Sing Yeh (Tim Clark). Third was Danny Shum Chap-shing's exciting prospect Fionn's Treasure (Zac Purton), who is two from two, but hasn't been sighted since beating a group of quality youngsters in the Griffin Trophy two months back. The form out of that race looks solid, Bear Hero, Wah May Star, Medallist and Flying Unicorn were among the beaten brigade, and the three-year-old looks well-placed on a mark of 70. He showed good gate speed, and sat out side the lead in a relaxed fashion. Outside him in fourth was Tony Cruz's California Choice, who looks primed for a return bout with Ambitious Dragon and a tilt at back-to-back Hong Kong Gold Cup next week. The diminutive grey hit the track looking like a fresh horse, his demeanour bright, but was given an easy time of it by Chadwick. He settled last, as is his usual pattern, and rattled off some nice sectionals when slipped rein in the straight. Mentor is another of Size's endless array of potential stars, and the three-year-old lived up to his three from four record in the final heat. Mentor was under strong hold by Whyte as he sat at the girth of Regency Luck all the way to the line. Trial results First trial - 1,200m (dirt): 1, GLORIOUS DAYS (D. Whyte); 2, Tai Sing Yeh (T. Clark); 3, Fionn's Treasure (Z. Purton). Others (in finishing order): California Memory, Shahjee, Keen Marie, Vital Flyer, Carry The Zeal, Healthy Manner. Time: 1:11.63. Distances: Neck; 11/2 lengths. Winner trained by J. Size. Second trial - 1,200m (dirt): 1, CAN DO (M. Du Plessis); 2, Penglai Xianzi (M. Chadwick); 3, Earl of Leitrim (D. Whyte). Others: Eternal Fame, Ekraar Emperor, Friends Support, Dragon Victory. Time: 1:11.12. Distances: 21/2 lengths; 23/4 lengths. Winner trained by J. Size. Third trial - 1,200m (dirt): 1, REGENCY LUCK (M. Chadwick); 2, Mentor (D. Whyte); 3, Interchina Star (O. Doleuze). Others: Viva Dolphin, Craig's Pride, Young Happy, Easy Job, World Way. Time: 1:12.09. Distances: Neck; Neck. Winner trained by A. S. Cruz.