Officially ranked as the world's best Flat horse after his superb victory in the King George VI And Queen Elizabeth Stakes, Harbinger, has been retired from racing after fracturing his near-fore cannon bone during a routine gallop on Saturday in Newmarket.
In a statement given on behalf of Harbinger's owners, the Admiral Rous Syndicate, Harry Herbert, racing manager for Highclere Thoroughbred Racing said, "It is with regret that it has been decided to retire Harbinger from racing."
Although the surgery on Saturday night was successful, his connections thought it was too much of a gamble to put the Sir Michael Stoute charge back on 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 crowning achievement was his 11 length victory in last month's King George at Ascot, with his next performance due in the Juddmonte International at York, followed by a probable start in the Prix de l'Arc de Triomphe, which for both races he had been a clear favourite.
Herbert also said, ''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.''