Canada's standout trainer is an American born in Indianapolis into a racing family. In 2011, Casse won his fifth straight and sixth overall training title at Woodbine in suburban Toronto with a record 119 victories, which was nearly double the number compiled by the runner-up. Among them were 13 stakes victories, including the Grey Stakes, in which Casse saddled the top three finishers. Casse's father, Norman Sr., retired as the chairman of the board of the Ocala Breeders' Sales in 2006 and is a 40-year-plus veteran of Thoroughbred owning, breeding and training.
Casse is the former private trainer and operations director for the massive Mockingbird Farm, which owner Harry Mangurian dispersed in 1999. Since moving to Canada, Casse has won three Sovereign Awards as Canada's top trainer and is a finalist for 2011. He won his titles in consecutive years, 2006 to 2008, a record. Six of his trainees are Sovereign Award winners and have a combined nine trophies among them, including 2007 Three-Year-Old Filly, Turf Female, and Horse of the Year Sealy Hill. Casse's son, Norman, is his top assistant.
In 2015, Casse won his first Breeders' Cup race when Catch a Glimpse won the Breeders' Cup Juvenile Fillies Turf. The next day he won the Breeders' Cup Mile with filly Tepin.