Jack d'Or was born in 2018. He is by Maurice out of Ravarino by Unbridled's Song.
Making full use of his sharp early speed, he made all the running in the Grade 1 Osaka Hai, holding off the likes of Grade 1 winners Stars on Earth and Danon the Kid in a race record time of 1:57.4 over 2000 meters on turf. He also won the Grade 2 Sapporo Kinen, defeating Dubai Turf winner and future Saudi Cup winner Panthalassa, and the Grade 2 Kinko Sho, setting a course record time of 1:57.2 for 2000 meters on turf at Chukyo.
Jack d'Or entered stud in Japan in 2025.