Henry Cecil, who trained unbeaten superstar Frankel and was one of British horse racing's greatest trainers in a career spanning nearly half a century, died Tuesday following a long battle with cancer. He was 70.
Cecil's death was announced on the website of Warren Place Stables, where the Scotsman worked as a trainer for 44 years.
Knighted by Queen Elizabeth II in 2011, Cecil was champion trainer in Britain 10 times. He capped his career by training one of racing's all-time great horses, Frankel, who was retired last year after winning all 14 of his races.
''His unique talents as one of Britain's greatest racehorse trainers, epitomized by his successes with Frankel, have played a major part in growing the sport's profile around the world, for which we will be forever in his debt,'' said Rod Street, chief executive of the British Champions Series.
The popular Cecil, who hailed from an aristocratic background and started his racing career as an assistant to his stepfather, was diagnosed with stomach cancer in 2006. He looked frail in his last few public appearances, speaking in a whisper.
After capturing his first classic winner at the 2,000 Guineas with Bolkonski in 1975, he trained four Derby winners and the same number of winners in the St. Leger.
In 1985, Cecil's Oh So Sharp became the first filly since 1955 to win English racing's three classics - the 1,000 Guineas, Oaks and St. Leger.
American jockey Steve Cauthen rode Oh So Sharp to England's Triple Crown in 1985 at the start of their successful six-year partnership with Cecil.
''He was a super intelligent guy and really knew how to place his horses,'' Cauthen said. ''He tried to have fun. The atmosphere during most of the time I was up at Warren Place was just fantastic.
''It was all due to him. It was a team effort but everyone looked to him. He was the one making decisions about where to run the horses.''
A minute's silence was held before each of the four meetings in Britain on Tuesday. More tributes are expected next week at Royal Ascot where Cecil claimed a record 75 victories.
''His record as a trainer was one of almost unparalleled achievement, but more than that he generated a level of affection from both racing's participants and followers that few others in sport can ever have matched,'' British Horseracing Authority chairman Paul Roy said.
Cecil was born into a racing family and started off at 21 as assistant to his stepfather, the royal trainer Cecil Boyd-Rochfort.
When Boyd-Rochford retired in 1968, Cecil took over his stables and the first of 10 champion trainer titles came in 1976.
But there were low points later on. Sheikh Mohammed removed all of his horses from Cecil's Warren Place yard in 1995, and an acrimonious split with jockey Kieren Fallon came four years later.
By 2000, Cecil's career faltered and there was speculation he could retire.
But Cecil bounced back, claiming 25 British winners in 2006. The following year, Light Shift won the Oaks for Cecil's first classic win since 1999.
A series of other Group One triumphs followed, with Frankel providing a fitting finale to Cecil's stellar training career by winning all 14 races before being declared among the best racehorses of all time.
''He went through a rough patch, but he came back,'' Cauthen said. ''To have a horse like Frankel and finish off his career when he wasn't in great health was incredible. He did a perfect job in making Frankel the horse he was.''
The British Horseracing Authority has granted a temporary license to Cecil's wife, Jane.
He is survived by two children from his first marriage, Katie and Noel, and son Jake from his second marriage.
