Ippei Mizuhara -- Shohei Ohtani's former interpreter -- just showed up to court and pleaded guilty to two federal charges ... stemming from allegations he stole from the MLB superstar in order to pay off gambling debts.
The 39-year-old hit a Santa Ana, CA courthouse early Tuesday morning ... and was mobbed by a throng of reporters as he made his way to the proceedings.
He did not, however, address the media as he traversed through all the cameras.