After graduating from university, Higashionna signed for the Canon Eagles ahead of the 2015 Top League season. He started 4 times and make 4 substitute appearances in his rookie year. In 2016 he firmly established himself as a regular in the starting XV, starting all 9 of Canon's games prior to the mid-season break for the November internationals.[4]
International
A strong showing in his first Top League season saw Higashionna earn his first cap for Japan during the 2016 Asia Rugby Championship. Higashionna debuted in an 85-0 win against South Korea on 30 April 2016. The following week he made his first start at international level in a victory away to Hong Kong.
After earning 3 caps during the Asian Rugby Championship, Higashionna made his first appearance against non-Asian opposition during the 2016 end-of-year rugby union internationals. Called up as an injury replacement midway through the tour, he made 1 appearance as a second-half replacement in the 38-25 defeat to Fiji on 26 November 2016.[1]