ARCADIA, Calif. - Friday was far from a perfect day for Aidan O’Brien-trained 2-year-old colts at Santa Anita. And still O’Brien and jockey Ryan Moore won the Grade 1, $1 million Breeders’ Cup Juvenile Turf for the sixth time, Unquestionable proving much the best under a flawless ride from Moore.  Unquestionable, when he finally changed leads at about the furlong grounds, cruised past pace-pressing My Boy Prince and was going considerably better at the finish than his stablemate Mountain Bear, who rallied from far back to nab second. My Boy Prince held third, while his Mark Casse-trained stablemate Can Group finished fourth. The winning margin was 1 1/2 lengths.  Mountain Bear pulled up lame in a foreleg and was taken off the racecourse in a horse ambulance. O’Brien said the colt had suffered a non-displaced condylar fracture, a serious injury that did not appear to be life-threatening.  “He’ll get a cast on for four weeks and should be fine. He’s down at the barn and settled in there,” O’Brien said in a post-race press conference.  All this came about nine hours after River Tiber, who probably would have been favored in the Juvenile Turf, was scratched by Breeders’ Cup veterinarians.   “Listen, we were sorry to see him go out, but rules are rules,” O’Brien said. “We thought he was ready to run; obviously, the vets didn’t agree, and it’s their job. We accept that.”  Moore had been booked to ride River Tiber but moved to Unquestionable, originally the mount of Frankie Dettori, after the scratch.  “He was our number one,” part-owner Michael Tabor said of River Tiber, “but having said that, there wasn’t much between the two.”  :: Breeders' Cup Shop: DRF Past Performances available now Unquestionable (86 Beyer Speed Figure) broke from post 7, and while Moore was coy about pre-race tactical plans, My Boy Prince looked on paper like the race’s lone speed. Moore rode Unquestionable hard out of the gate, probably aiming to keep the expected pacesetter in range. Instead, Air Recruit was sent hard from post 1 to come inside My Boy Prince and take an early lead. That left a clear passage down to the fence, and Moore quickly steered left to take it, setting into a perfect trip saving ground behind the speed.  “That wasn’t the plan, but I was very happy with where I was,” Moore said.  Air Recruit, up by a length, led My Boy Prince through splits of 22.26 and 46.72, fast but not entirely compromising over a lively course. Around the far turn, Unquestionable was traveling sweetly, and it seemed just a matter of where and how Moore might find room. He found it when Stay Hot, racing outside and behind My Boy Prince, began fading as the field turned into the homestretch. Moore angled outside the two pace players and Unquestionable edged up to them, dashing clear once he switched his leads, coming home in 1:33.65 for the mile under vigorous encouragement. He was given a Beyer Speed Figure of 86. “When he gets to the front, he thinks he’s done enough,” Moore said. “But he’s got speed, and that helps when you come in here.”  Mountain Bear had a head on My Boy Prince, who was a half-length better than Can Group. Then came Agate Road, Tok Tok, Air Recruit, Endlessly, Carson’s Run, Stay Hot, and Fulmineo. The winner paid $5 as the favorite.  Unquestionable wore the silks of Al Shaqab Racing, which owns him with Tabor, Westerberg, Mrs. John Magnier, and Derrick Smith. Unquestionable is by Wootton Bassett out of Strawberry Lace, by Sea The Stars. Moore said to watch out for the horse next year.  “He's quite a long, scopey horse, and a lot of Wootton Bassetts, they ride like horses that are going to be better as 3-year-olds,” said Moore.  O’Brien sent Unquestionable to France to finish second last month in the Group 1 Prix Jean-Luc Lagardere. That race not only set him up for the Juvenile Turf, but O’Brien already was thinking ahead to 2024, suggesting after Friday’s race that Unquestionable could be a horse for the French 2000 Guineas next spring.  Unquestionable absolutely was a horse for the Juvenile Turf. Maybe his scratched stablemate would have beaten him – but that is a question that never will be answered.  :: Want to learn more about handicapping and wagering? Check out DRF's Handicapping 101 and Wagering 101 pages.