Sovereignty (Into Mischief), the 2025 GI Kentucky Derby-winning Horse of the Year and the recent 3-1 future-wager favorite to win the GI Longines Breeders' Cup Classic, will miss his planned next start in the Sept. 18 GI Jockey Club Gold Cup.David Grening of Daily Racing Form reported the news Friday, citing confirmation by Sovereignty's trainer, Bill Mott.The defection was not entirely unexpected, Grening reported, noting “an abscess in his hind left foot that forced him to miss two workouts and has kept him off the track for more than one week.”The defection deflates some of the star power on the opening-day program of the new Belmont Park, which will host its first races since 2023 after a $455-million rebuild of the racing surfaces, grandstand, clubhouse and backyard saddling area.The new plan is to train Sovereignty up to the Oct. 31 Classic at Keeneland, Mott told Grening.Sovereignty is 1-for-3 this year, having run second in the Apr. 18 GII Oaklawn Handicap and third in the June 27 GI Stephen Foster Stakes before winning the Aug. 8 GI Whitney Stakes by 4 3/4 lengths.The post Report: Sovereignty Out Of GI Jockey Club Gold Cup appeared first on TDN | Thoroughbred Daily News | Horse Racing News, Results and Video | Thoroughbred Breeding and Auctions.