Shohei Ohtani's wife couldn't contain her excitement when the MLB superstar earned the first hit of his Dodger career ... cheering on her man from the stands throughout his big debut!!
Mamiko Tanaka -- who was recently revealed as the Japanese athlete's partner -- was present for L.A.'s season opener against the San Diego Padres in Seoul, South Korea on Wednesday ... and there was plenty to be happy about.
Ohtani logged the first hit of the contest in the third inning ... hitting a line drive to right field for a single.