Shin Emperor

2023: Two-year-old season

Shin Emperor made his debut at Tokyo Racecourse over a distance of 1800 meters with Takeshi Yokoyama as his jockey.^[7] He would run the race in third for most of the race before taking over the lead on the home stretch, winning the race with a three length lead.^[12] Following the race, it was announced that Shin Emperor would contest the Kyoto Nisai Stakes, with João Moreira as his jockey.^[13]

At the Kyoto Nisai Stakes, he had a poor start and ran in the back of the pack. However, Shin Emperor would pass through the pack on the final stretch and clinched his first graded race win. This victory coincided with the death of his dam, Starlet's Sister, who died from colic the day prior to the race.^[14][15] This race also marked the first time a French bred horse won a JRA graded race since Daiwa Caerleon [ja] won the Fuji Stakes in 2008.^[15]

Shin Emperor finished the season with his first Grade I race, the Hopeful Stakes, where he lost to Regaleira by 3/4 lengths.^[16]

2024: Three-year-old season

Shin Emperor started the season with the Yayoi Sho, which is ran in the same course and distance as the Satsuki Shō, the first leg of the Japanese Triple Crown. In the race he was positioned in the middle of the pack before making his push to take the lead at the third corner. He was able to take over the front runner Sirius Colt [ja], he was unable to catch up to the winner Cosmo Kuranda [ja], who would win the race with a 1 1/4 length lead against the horse.^[17]

As the horse finished second in the Yayoi Sho, he was given an entry slot for the Satsuki Shō, which would be his next race. From this race onwards, Ryusei Sakai would become the horse's main jockey.^[18] During the race, the horse ran in the middle of the pack even as the pace was extremely fast due to how fast the front runner, Meisho Tabaru, was running. He was able to come up to 4th, but was passed by Urban Chic and ultimately finished the race at 5th place.^[19][20]

After this, the horse was entered in to the second leg of the Japanese Triple Crown, the Tōkyō Yūshun. During the race, the horse ran in the middle of the pack, before attempting to take the lead. However, he was not able to catch up to the winner, Danon Decile, nor the runner-up, Justin Milano.^[21] After this race, it was announced that the horse would be sent to Europe, where he would race the Prix de l'Arc de Triomphe, the same race Sottsass won, after using the Irish Champion Stakes as a step race.^[22][23]

In the Irish Champion Stakes, he ran in fourth for most of the race, but was unable to push forward as Economics and Auguste Rodin had been in front of him. Despite this, the horse moved on to Auguste Rodin's outside on the home stretch and finished third behind those two races, narrowly fending off Los Angeles [ja].^[24] At the Prix de l'Arc de Triomphe, he finished 12th after being unable to catch up to the lead.^[25]

After returning to Japan, he was entered in to the Japan Cup. The horse was only the eighth favored to win, but during the race he became the front runner after making a good start. Making the race's pace slow, the horse's lead was contested by Do Deuce and Durezza. While the lead was taken by Do Deuce, Shin Emperor and Durezza kept contesting the second place to the wire; ultimately finishing second in a dead heat with Durezza.^[26] After the race, the horse would take the rest of the year off, preparing to enter races in the Middle East for the following year.^[27]

2025: Four-year-old season

Shin Emperor started the season with the Neom Turf Cup, an undercard of the Saudi Cup Night. During the race, Shin Emperor took the lead early on and held on to it, with the horse winning the race with a length and 3/4 lead, marking his first win since the Kyoto Nisai Stakes in 2023 as well as his first win abroad.^[28][29]

He was then entered in to the Dubai Sheema Classic, where he once again became the front runner. However, the horse lost momentum at the final stretch, and finished seventh behind Danon Decile.^[30] After returning to Japan, Yahagi announced that the horse would once again run the Irish Champion Stakes and the l'Arc.^[31]

On September 14, Shin Emperor was entered in to the Irish Champion Stakes, only to finish sixth behind Delacroix. After the race, the horse underwent a medical examination, where it was revealed that the horse suffered from asthma and lung hemorrhage. As a result, plans to enter the l'Arc was scrapped and the horse was returned to Japan.^[32]

After returning to Japan, the horse entered in the Japan Cup and the Arima Kinen, but finished 8th and 14th respectively.^[33][34]

2026: Five-year-old season

On January 2, Yahagi announced the horse would start his five-year-old season with the Neom Turf Cup, the same race he won the previous year.^[35] In the race, the horse stayed intact with the leader group on the inside before switching to the outside track in which he unleashed his final sprint to finish in fourth place.^[36][37]