[4] Hayashi started his youth football career with Sagan Tosu U-15s and quickly made his way up to the U-18s, being named as a substitute for them in 2016 at just 15.
[10] In his final year, Hayashi was named captain and helped Meiji University win the league, despite fracturing his metatarsal midway through the season.
[16] He made 32 appearances and scored two goals across all competitions in his debut season, but was unable to prevent Yokohama FC from being relegated to the J2 League.
In January 2024, it was announced that Hayashi would be transferring to newly promoted J1 League club Machida Zelvia ahead of the 2024 season.
Hayashi is a right-footed left back and has named one of his favourite foreign players as João Cancelo.