He previously played for the Fukuoka SoftBank Hawks of Nippon Professional Baseball.

[2] On July 14, 2017, Masago debuted in the Pacific League against the Hokkaido Nippon-Ham Fighters.

[3] And on August 3, He recorded his first Home run against the Orix Buffaloes.

And he recorded a 26 stolen bases in the Western League and he was honored with the 2019 Western League Most Stolen base Leader Award at the NPB AWARD 2019.

[10] And he was honored for the Most valuable player and the Best Nine Award at the 2016 U-23 Baseball World Cup.