Frankel on one end, Black Caviar on the other: As far as bookends go, the Royal Ascot meeting has done pretty well by itself. The two most famous horses in the world – Black Caviar unbeaten in her 21 starts, Frankel in his 10 – are the stars of Royal Ascot 2012. Frankel goes in the Queen Anne Stakes on Tuesday’s opening card, while Black Caviar will highlight Saturday’s closing-day program in the Diamond Jubilee Stakes. The five-day meet features seven Group 1 races in all, daily processions of royalty into the racecourse, and, of course, tall goofy hats at which most of the rest of the world can giggle. Tuesday’s opening-day card is, top to bottom, the best racing of the meeting, with two other Group 1’s, the St. James's Palace and the King’s Stand, supporting the Queen Anne. But it is the Queen Anne, the first race of the meeting, that will attract the most attention. That’s because of the presence of Frankel, the best horse in the world according to the World Thoroughbred Rankings created by the International Federation of Horseracing Authorities. Almost a distant memory at this point is the injury scare this spring that briefly seemed to threaten Frankel’s career. The colt was exercising at Newmarket when he rapped the back of his front leg with a hind hoof, the injury putting his training on hold while tests were performed and the affected area closely monitored. The problem turned out to be merely superficial, and Frankel was ready enough for his first start of 2012 to bury five foes in the Group 1 J.T. Lockinge Stakes on May 19 at Newbury. Frankel won that race by five lengths, the seventh time he has recorded a win of four lengths or greater, and he will be expected to turn in a similarly dominant performance Tuesday. Frankel came nearest to defeat on opening day of Royal Ascot in 2011, winning the St. James’s Palace Stakes by only three-quarters of a length, but the ride from jockey Tom Queally that day was widely blamed for the close call. Nothing similar has since occurred, and at age 2, Frankel won the Royal Lodge over Ascot’s straight-course mile by 10 lengths. Frankel raced only on good or good-to-firm courses last year at 3, but as of this weekend the ground at Ascot was called soft, and though fair weather before race day should quicken the going somewhat, the turf will be something less than firm. That should prove no obstacle to Frankel, who will have stable-mate Bullet Train serve as a pacemaker as he successfully did in the Lockinge. Frankel would have to falter to lose Tuesday, since none of his opponents have ever run well enough to beat him at anything close to his best. The opposition is expected to include Excelebration, the Lockinge runner-up who is no match for the favorite, and Strong Suit, who will make his first start since finishing unplaced in the Breeders’ Cup Mile. While England waits excitedly to see Australia’s top sprinter, Black Caviar, in the Diamond Jubilee, another Aussie, Ortensia, is fully capable of landing the King’s Stand over five furlongs. When last seeing action, Ortensia swept powerfully down the middle of the Meydan grass course to impressively capture the Meydan Sprint on Dubai World Cup night. There is nothing like a Frankel in this year’s St. James’s Palace Stakes, a 3-year-old restricted race. Aidan O’Brien might have the favorite in Irish 2000 Guineas winner Power, and could also start Kentucky Derby flop Daddy Long Legs.