Justin Milano debuted on November 11, 2023, at the Tokyo Racecourse in a two-year-old newcomer race on turf at a distance of 2,000 meters, ridden by Tom Marquand.

Ridden by Keita Tosaki, he settled in just behind the leader and moved forward after entering the final stretch in response to Tosaki's urging to take the lead, managing to successfully hold off last year's Asahi Hai Futurity Stakes winner Jantar Mantar to win by one and a half horse lengths.

[7] Canceling the previous plan to enter the Epsom Derby, he was instead scheduled to race at the Satsuki Shō (Japanese 2000 Guineas) on April 14.

After settling in near the front throughout the early and middle parts of the race, he moved up in the final straight but failed to pass Danon Decile, who had burst out from the inner lane near the fence.

[13][14]After the Tōkyō Yūshun, it was initially announced that the horse would be entered in to the Autumn Tenno Sho rather than the Kikuka-shō, the third leg of the Triple Crown.

[16] It was ultimately decided on November 14 that the horse would be retired to stand stud at the Breeders Stallion Station [ja] in Hidaka, Hokkaido.