After Graduating from Collage, Sensei Yaguchi worked for an engineering firm for a few months before leaving the job to enroll in the second class of the JKA Instructor Training, with Sensei Enoeda, Sensei Kana, Sensei Zawa, Sensei Mikami, Sensei Shirai and Sensei Asai among his fellow students. The instructor was Master Nakayama, who was assisted by Sensei Okazaki and Sensei Nishiyama. Sensei Yaguchi's Nidan examination was the last one personally presided over by Master Funakoshi.

Sensei Yaguchi remained in Tokyo after graduating from the JKA Instructor Training Program and taught for the JKA. In 1965 he left Japan and traveled to the United States first visiting Los Angeles and then Denver Colorado. In 1966 he returned to Los Angeles where he stayed for 6 years. before moving to Denver where he still lives today.

Yaguchi Sensei emphasizes the individual student's understanding of their own body in order to draw the best from each. His focus goes beyond technique to include character development and determination. The achievements of some of his students--Sensei James Field, Sensei Frank Smith and Sensei Masahiko Tanaka --bear witness to Yaguchi Sensei's well earned reputation as the best Kumite Coach in the history of the JKA.