Trained by William Haggas, the four-year-old had not been seen in competitive action since winning at Kempton in November, but was nevertheless prominent in the market at 11-2.
For a moment early in the straight it looked as though Kim Bailey’s Ajero had slipped the field, but Candleford joined him approaching the final furlong before rocketing clear.
The Queen’s 4-1 joint-favourite Just Fine never threatened to land a telling blow and was well beaten.
Haggas said: "He loves going right handed and won a nice race in the autumn. I thought going a mile and a half on fast ground would prove right up his street.
"I actually thought all through the winter I would win the Duke Of Edinburgh, but not with him. I didn’t think he would get in, but I was wrong.
"One person I’m thinking of right now is Alison Samuel, who rides him every day. She will be in tears for a week."
The winner is owned by former England cricketer Craig Kieswetter’s Barnane Stud.Start a FREE one-month trial of Racing TV today and enjoy every race live from 62 British and Irish racecourses. Click here for more details.
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