Eishin Flash debuted at a debut race for 2 year olds of 1800 meters (turf) on July 12 at Hanshin, where the horse finished in 6th place with Yuichi Fukunaga riding him. Two months later, the horse won his first race at another maiden race held at Kyoto, this time with Hiroyuki Uchida [ja] as his jockey. Fukunaga once again became the horse's jockey later at the Hagi Stakes but finished 3rd. Later on, with Uchida back as jockey, Eishin Flash won the Erika Sho [ja], leading to Uchida becoming the main jockey.[5]
2010: Three-year old season
At the Keisei Hai, because Uchida was injured in another race, Norihiro Yokoyama briefly took over the role of jocket. Eishin Flash was nonetheless the most favored to win owing to the Erika Sho victory, and subsequently won the race, making it his first graded race victory. Later, the horse was scheduled to run the Wakaba Stakes [ja] but was forced to skip the race as the horse contracted pneumonia.[6] The horse was then sent to the Satsuki Shō, where he was the 11th most favored to win but managed to finish 3rd, securing priority entry to the Japanese Derby.
At the 77th Tokyo Yushun (Japanese Derby) the horse was the 7th most favored to win. The horse ran in the middle of the pack, which covered the first 1000 meters at a slow pace of 1:01.6 and the first mile 1:41.6. As the pack entered the final stretch, the horse took the lead, running the last three furlongs at a record breaking 32.7 seconds, and held on to the lead across the finish line even as Rose Kingdom closed in. This marked the first Tokyo Yushun victory for both Uchida, trainer Hideaki Fujiwara, and owner Toyomitsu Hirai. ==
Later on in Autumn, the horse was entered in to the Kobe Shimbun Hai with the Kikka Sho in mind. However, the horse was beaten by the winner, Rose Kingdom, by a neck. The horse was still scheduled to run, but a few days before the race, the vet that checked the horse noticed symptoms of muscle pain and the plans to enter the horse in the race were scrapped at the last minute.[7] Later on, the horse was sent to run in the Japan Cup and Arima Kinen but finished unplaced in both races.[5]
2011: Four-year old season
Eishin Flash started the 2011 season with the Osaka Hai, but finished third behind Hiruno d'Amour [ja]. Later on, the horse ran the Spring Tenno Sho, but finished 2nd to Hiruno d'Amour again. Later at Takarazuka Kinen, Katsumi Ando [ja] took over the role of jockey following another accident that left Uchida injured. At Takarazuka, the horse finished third behind Earnestly [ja].[5]
In Autumn, the horse was entered in to the Autumn Tenno Sho, with Christophe Lemaire as jockey, where he finished 6th. The horse was unplaced in Japan Cup, and at Arima Kinen the horse finished 2nd behind Orfevre.[5]
2012: Five-year old season
Eishin Flash was one of three Japanese horses that was entered in to that year's Dubai World Cup, together with Transcend [ja] and Smart Falcon [ja], where he finished 6th, which was the best of those three. After returning to Japan, he was entered in to the Takarazuka Kinen with Uchida returning as jockey, but finished 6th, with the 5th place horse beating him by 5 lengths. After a summer break, the horse started off unplaced in the Mainichi Okan, but at the Autumn Tenno Sho, which became the first Tenno Sho in 7 years to be attended by EmperorAkihito and Empress Michiko, the horse won his first race in 13 starts, and his second Grade I race since the Japanese Derby. Following the race, Eishin Flash's jockey, Mirco Demuro, dismounted from the horse, removed his helmet, and knelt in front of the Emperor and Empress.[8]
On the horse's final race of the season, the Arima Kinen, Demuro was diagnosed with ureteral stones and Kousei Miura took over the role of jockey on the day of the race. At the race, the horse briefly took over the lead briefly but finished fourth.[5]
2013: Six-year old season
As Toyomitsu Hirai passed away on the March 2, ownership of the horse was transferred to Katsuhiko, his second born son. As for the horse himself, the horse started the season with the Osaka Hai on March 31, but finished 3rd behind Orfevre. After this, the horse was sent to Hong Kong to race the Queen Elizabeth II Cup with Mirco Demuro, where he finished 3rd behind Military Attack, who finished a length and three-quarters in front of him. After a five and a half months long break, he was entered in to the Mainichi Okan and won. He was then entered to the Tenno Sho (Autumn) to win the race once again, but finished third. He later finished 10th in the Japan Cup. He was planned to run in the Arima Kinen as his final race, but his gait showed signs of problems, and as a result the horse was scratched. In spite of this, a retirement ceremony was still held at Nakayama Racecourse.[9][10]
Stud career
Following his retirement, he stood stud at Shadai Stallion Station,[10] before being transferred to Lex Stud in late 2018.[11] As of 2024, the horse is standing stud at Lex Stud for a service fee of 800,000 JPY.[12]