Essential Quality is 2-1 favorite for the Kentucky Derby

Jockey Luis Saez rides Essential Quality to win the Breeders' Cup Juvenile horse race at Keeneland Race Course in Lexington, Ky., in this Friday, Nov. 6, 2020, file photo. Essential Quality is expected to be the first gray horse favored to win the Kentucky Derby in 25 years. (AP Photo/Michael Conroy, File)

LOUISVILLE, Ky. — With the rail still open and Kentucky Derby post positions dwindling, Brad Cox grew anxious about the most notable of his two horses drawing the least desired spot.