It was announced on the 20th by the Japan Bloodhorse Breeders' Association (JBBA) that Ishino Sunday, the winner of the 1996 G1 Satsuki Sho, passed away from old age on the 18th at the age of 31.

Ishino Sunday debuted in 1995 under the care of the Yamauchi stable. He captured his first graded stakes title in the G1 Satsuki Sho and went on to win the NAR local graded stakes Derby Grand Prix that same year, excelling on both turf and dirt. He recorded 6 wins in 22 starts, including 3 graded stakes victories. After retiring in 1998, Ishino Sunday began his stud career in 1999 at JBBA's Shimousa Farm. He stood at JBBA's Shichinohe, Kyusyu, and Shizunai farms until 2016.

Trainer Hirofumi Shii, who was the colt's primary jockey and who secured his first G1 victory alongside Ishino Sunday in the Satsuki Sho, reflected, "He lived a long and fulfilling life. As one of the early progeny of Sunday Silence, he gave me confidence as a young rider, being with him from the start of his career. He won the Satsuki Sho, and even as an older horse, he claimed victory in the G3 Kyoto Kimpai. He taught me so much." Shii also added, "Though he didn't sire any stakes winners, I heard that at Shizunai, he served almost like a mentor. I hope he rests peacefully."

Shigeki Yusa, the manager of Shizunai Stallion Station, commented, "He truly embodied the saying 'A sound horse is a good horse,' living a long life to the age of 31. He was an excellent mentor, nurturing many, and was loved by many fans. He spent his final years peacefully, and I am deeply grateful to everyone who supported him."