Godolphin Racing's Dubai Millennium, who was retired Saturday after breaking a leg during a workout in Newmarket, England, underwent successful surgery Sunday to correct the lateral condylar fracture of his right hind leg. Sheikh Mohammed, who races under the Godolphin banner, was on hand at Beaufort Cottage Equine Hospital for the entire 5 1/2-hour operation performed by Dr. Dan Hawkins, chief surgeon at the Dubai Equine HospitalAccording to the Godolphin Website, the injury came just after Sheikh Mohammed offered a challenge to Michael Tabor, owner of Montjeu, for a $6-million match race. The race between Dubai Millennium and Montjeu would have been at 1 1/4 miles.Dubai Millennium had been impressive in both of his starts this year, leading Sheikh Mohammed to conclude the colt was the best horse he has owned.The 4-year-old son of Seeking the Gold won the Dubai World Cup at Nad Al Sheba, Dubai and then was ridden by Jerry Bailey to an unchallenged eight-length victory in the Prince Of Wales's Stakes at Royal Ascot. Following that race, his connections said Dubai Millennium would be pointed toward the Breeders' Cup at Churchill Downs, providing American audiences with an opportunity to see the colt.Dubai Millennium retires with nine wins in 10 starts, four of them in group I company. His only defeat came in the 1999 Vodafone Derby at Epsom when 12 furlongs proved too far. He was originally called Yaazer but the name change came before he first ran as a 2-year-old, with the 2000 Dubai World Cup in mind.