Black Caviar remained undefeated winning the Group 1 Diamond Jubilee Stakes on Saturday, closing day at Royal Ascot. Of that there can be no dispute. The devil is in the details, though, and the way in which Black Caviar won for the 22nd time in her career should lend itself to international racing chatter for weeks, if not longer. Black Caviar’s winning margin, a nose, was the shortest in her career, and just the second time a horse has been within one length of her at the finish, but jockey Luke Nolen must shoulder some of the blame for the race's closeness. Nolen, Black Caviar’s regular rider back home in Australia, got Black Caviar out of the gates in good order from the outside post in a 15-horse field. Soul set the pace, while Black Caviar, racing third and in the clear, stalked and appeared fairly comfortable. Midway through the six-furlong race, Nolen subtly asked for a little more run and got it, Black Caviar inching toward the lead. But when Nolen called on his mount perhaps 300 yards from the finish, Black Caviar failed to deliver her usual brilliant acceleration. Still, Black Caviar edged clear and appeared to be on the way to a slogging if definitive victory when, with 50 yards to run, Nolen stopped riding, perhaps misjudging the finish. Black Caviar relaxed and in that moment was nearly caught by onrushing Moonlight Cloud, who came up just inches short. Restiadargent finished another neck back in third. Time for the six furlongs was 1:14.20. Nolen said afterward he’d underestimated the testing nature of the Ascot turf, which was laboring and slow-playing Saturday, assuming that Black Caviar had done enough to win. Whatever the specifics of his mistake, Nolen was fortunate to avoid the far greater ignominy that would have descended had his miscue cost Black Caviar her unbeaten career. Pilot error aside, Black Caviar did not look like her best self racing half a world from home while shipping for the first time. The 6-year-old mare reportedly had travelled well but certainly did not appear to produce a top performance over a course that might’ve been wetter than any she’d raced over before. “Black Caviar was not 100 percent in the race,” said Peter Moody, who trains Black Caviar for a 10-owner partnership. “We’ll look at her when we got home, and she might be retired.” The trip home will come immediately, with Black Caviar set to depart England on Sunday. She leaves with her perfect record intact while failing to deliver the kind of jaw-dropping performance Frankel turned in winning the Group 1 Queen Anne Stakes on opening day at Royal Ascot. Frankel, undefeated in 11 starts, and Black Caviar have been the two highest-rated performers in the world this year. At Royal Ascot, Frankel staged a show featuring utter brilliance. To Black Caviar, it was left to demonstrate the heart that propels a champion.