Gatsby could be great Champion trainer Aidan O'Brien had his first winner of this year's Galway Festival when The Great Gatsby landed some hefty wagers in the Dawn Hi And Low Maiden over an extended mile on Saturday.Narrowly defeated when running very green on his debut at Tipperary, the son of Sadler's Wells looked an exciting prospect as he went away in the last half furlong from the front-running Akash in the hands of Seamus Heffernan.Well backed from evens to 4-6, this handsome colt took his time to get into top gear but was going away at the finish to score by three and a half lengths and looks a horse to follow.'He is still very inexperienced, but I had plenty of horse under me a furlong out. He should go on to better things,' said Heffernan.The Great Gatsby's initial victory came less than 24-hours after his older half-sister Marigold had taken Friday night's featured Guinness Handicap for the Willie Mullins stable.Feabhas won her second race at the Festival when she defied a 5lb penalty in the EBF Premier Nursery for her trainer-breeder Jim Bolger.Successful in a seven-furlong maiden last Tuesday night, the daughter of Spectrum again stuck her head out well for jockey Kevin Manning to become his third winner of the week to put him on top of the Flat riders' table.Feabhas got home by a neck at 11-2 from the 10-1 chance Lady's Mantle.Paul Carberry is on the four-winner mark for the Festival following an impressive debut success over fences for champion trainer Noel Meade's Snob Wells in the opening Jockeys Association Beginners' Chase.Vatirisk, unplaced on soft ground on the Flat here on Monday faired much better back over t