Harbinger Retired Harbinger, officially rated the best Flat horse in the world, has been retired from racing. The brilliant winner of the King George VI And Queen Elizabeth Stakes fractured his near-fore cannon bone on the gallops in Newmarket on Saturday. Harry Herbert, racing manager for Highclere Thoroughbred Racing, said in a statement issued on behalf of the colt's owners, the Admiral Rous Syndicate: "It is with regret that it has been decided to retire Harbinger from racing." Harbinger underwent surgery on Saturday evening, but connections felt it was too much of a risk to return the Sir Michael Stoute-trained four-year-old to the racecourse. Herbert said: "Thanks to the professionalism of the veterinary surgeons, Bruce Bladon of O'Gorman Slater & Main, Andrew Bathe of Rossdale & Partners and Antony Clements of Baker & McVeigh, the operation which was undertaken at Rossdales Hospital in Newmarket has been very successful. "We are pleased to report that thankfully the horse is recovering well. The decision to retire Harbinger is based on the welfare of the horse which is paramount to all concerned. "The owners, for whom this is very sad, are naturally sorry that their great horse has had his racing career cut short.'' Harbinger's finest hour came when he won last month's King George at Ascot by 11 lengths. He was next scheduled to run in the Juddmonte International at York later this month, after which the Prix de l'Arc de Triomphe was on the agenda. The son of Dansili had been clear favourite for both races. Stoute's charge won his last four races, including the Hardwicke Stakes at Royal Ascot, and accrued over £770,000 in prize-money. Herbert added: ''Harbinger has given all concerned the ultimate thrill at the very highest level. "The highest-rated horse in the world, Harbinger won six of his nine starts and is undefeated this year. "In winning the Hardwicke Stakes at Royal Ascot so impressively and then producing one of the greatest performances of all time to win the King George VI and Queen Elizabeth Stakes by 11 lengths in record time, Harbinger has confirmed himself as one of the all-time greats.''