[5] These three victories earned Taniguchi the change to challenge the reigning WBO mini-flyweight champion Vic Saludar, in the latter's first title defense, on 26 February 2019.
[10] On 7 October 2021, the WBO ordered Wilfredo Méndez to make his third mini-flyweight title defense against the mandatory challenger Masataka Taniguchi.
Taniguchi upped his output in the eleventh round, forcing referee Nobuto Ikehara to stop the fight with a flurry of punches to which the cornered Méndez did not respond.
[13] Taniguchi was booked to make his first WBO mini-flyweight title defense against Kai Ishizawa on 22 April 2022, in the main event of PBX Phoenix Battle 87, which was broadcast as a pay per view by Abema TV.
Taniguchi retained the belt by an eleventh-round technical knockout, forcing a referee stoppage with a flurry of punches at the 2:29 minute mark of the penultimate round.
[16] Taniguchi is scheduled to make his second WBO championship defense against the one-time WBC mini-flyweight title challenger Melvin Jerusalem.
He was dropped with a one-two combination near the beginning of the round and remained unsteady on his feet despite beating the ten-count, which prompted referee Roberto Ramirez Jr. to wave the bout off.
[23] On 17 April 2024, Taniguchi's representatives Treasure Boxing Promotion held a press conference at the Watanabe Gym in Shinagawa to announce he would face Jaysever Abcede on 11 May 2024.
The contest will take place at the Paradise City Grand Ballroom in Incheon, South Korea, as an undercard fight for the flyweight bout between Hiroto Kyoguchi and Vince Paras.