[2] He enrolled in The Horse Racing School [ja] in 2013 to earn his jockey license, before graduating in 2016.

[11] Sakai won his first JRA Grade I race with Stunning Rose in the 2022 Shuka Sho, where they defeated Stars on Earth, who was the favored to win.

[12] Sakai then went on to win his second JRA Grade I race in a year with Dolce More [ja] when they won the Asahi Hai Futurity Stakes.

He and the horse would go on to win the Mile Championship Nambu Hai as well as the Champions Cup later that year.

[13] Following their consecutive wins at that year's Saudi and UAE Derbies,[14] Sakai and Forever Young headed to the 2024 Kentucky Derby, where they were beaten by Mystik Dan and Sierra Leone in a photo finish and finished third.