[4] He also made his first appearances in the Emperor's Cup, playing 90 minutes in both of their games and helping Toin to a narrow 4–3 defeat against J1 League club Shonan Bellmare.
[6] In December 2018, it was announced that Yamashita would be signing for Tohoku Soccer League team Iwaki FC for the 2019 season.
[7] He made his debut for the team in May in a 3–2 Emperor's Cup defeat to Sendai University and went on to make 10 appearances in his first season with the club, helping Iwaki to gain promotion to the Japan Football League.
[9] After an excellent season, Yamashita was named the league's MVP and was also inducted into the 2021 JFL Best XI.
[11] He made his J.League debut in a 1–1 draw with Kagoshima United and went on to play in every minute of every game throughout the season as he helped Iwaki to back-to-back promotions.