Horse racing-Australia lands English Derby for O'Brien

* Australia wins Derby at Epsom * Trainer O'Brien is first to win the race three years in a row (Adds details, quotes) June 7 (Reuters) - Aidan O'Brien's belief that his superbly-bred colt Australia was the best he has ever trained was fully vindicated when he landed the English Derby at Epsom on Saturday. Given a confident ride by the trainer's son Joseph O'Brien, 11-8 favourite Australia settled early, held a prominent position throughout before cruising to the front and holding off Kingston Hill (15-2) to win by one-and-a-quarter lengths. Ireland's O'Brien is the first trainer to win the Derby, the showpiece of English flat racing, in three successive years and was capturing the Classic for a fifth time following Galileo (2001), High Chaparral (2002), Camelot (2012) and Ruler of the World (2013). It was a second Derby triumph for jockey O'Brien, 21, who hailed the son of Galileo and 2004 Oaks winner Ouija Board as "the best". "Horses don't come any easier to ride than this one," he said. "I had a grand position and I was going easy coming down the hill. They went a nice even pace and I was cantering all the way. I maybe got there too soon and he had a look." O'Brien senior added: "We said what we thought - that he was very special always and to have the pace that he has for a Galileo is incredible." Australia won two of his three starts as a two-year old before finishing third on his seasonal return in Britain's first Classic of the season, the 2,000 Guineas at Newmarket last month. (Reporting by Justin Palmer; editing by Alan Baldwin)