Hikaru Sato
Following his departure from WWE, Tajiri returned to Japan, with All Japan announcing his first post-WWE booking for June 11. On July 30, Tajiri defeated Hikaru Sato to win the promotion's World Junior Heavyweight Championship. He lost the title to Último Dragón on August 27, before regaining it on October 21. His reign as Junior Heavyweight Champion lasted until February 3, 2018, when Atsushi Aoki won the championship from Tajiri. Tajiri defeated Jun Akiyama on July 15, 2018, to win the Gaora TV Championship. AJPW further pushed Tajiri as he and tag team partner Koji Iwamoto were entered into the 2018 Jr. Tag Battle of Glory tournament. The duo won four of the six first-round matches, then defeated Atsushi Aoki and Hikaru Sato in the finals to win the tournament.