(CNN) -- Under the watchful gaze of one monarch, a new king was crowned at Epsom Downs Saturday as the Aidan O'Brien-trained Ruler of the World dominated rivals to claim England's most prestigious race, the Epsom Derby.
But it was a day of disappointment for the pre-race favorite, Godolphin-owned Dawn Approach, who failed in his quest to add the Derby to his 2,000 Guineas triumph last month.
Queen Elizabeth, a regular Derby attendee, was among those who had gathered to see Dawn Approach attempt to become the 38th horse to win the first two legs of English racing's Triple Crown.
But his race was over within the first furlong as the Jim Bolger-trained colt appeared to crack under the pressure of a tactical early pace, pulling fiercely from the start and refusing to settle for jockey Kevin Manning.
After briefly hitting the front at the mile marker, the son of 2008 Epsom Derby winner New Approach faded badly and eventually finished second from last. His connections conceded it would probably be his last outing over a mile and a half.
But it was a different story for Ruler of the World, rated at 7/1 odds to win.
Joseph O'Brien, Ballydoyle's stable jockey and son of the trainer, had opted to ride the equally immodestly named Battle of Marengo, leaving the way clear for Ryan Moore to claim the ride on Ruler of the World.
Moore's faith in the chestnut colt paid off as he blasted home by one and a half lengths from a strong-finishing Libertarian, winner of last month's Dante Stakes. Galileo Rock was just a short head behind in third, with Battle of Marengo next to finish.
Acknowledging the first part of the race had been "messy," Moore said that Ruler of the World had quickened well rounding Tattenham Corner, adding that he thought the horse could get an even further trip in the future.
"He has got a real, likeable attitude," Moore said. "You have got to give credit to the horse. He really toughed it out and showed a very good attitude."
O'Brien thanked the horse's owners, John and Sue Magnier, Michael Tabor and Derrick Smith.
"We are so lucky to be in the position that we are in, to get such horses," he said. "They are incredibly bred horses and, even before they are mated, the dream is for this to happen."
Ruler of the World's triumph gave the Irish trainer a second consecutive win in this race and a fourth in total, while Moore has previously won on Workforce in 2010.
A son of super sire Galileo, Ruler of the World was, unusually, not raced at two years old. He is the first horse in such a position to win the Derby since 1993, and has enjoyed an undefeated three-year-old campaign over distances from 10 furlongs to a mile and a half.
His performance over the demanding Epsom course on just his third start suggests there could be plenty more to come from a horse whose very name seems to betoken greatness.