Shohei Ohtani (left) and translator Ippei Mizuhara (right) at an event in 2021
Shohei Ohtani (left) and translator Ippei Mizuhara (right) at an event in 2021 AFP

The US Justice Department investigation into Shohei Ohtani's former interpreter has painted a portrait of an insatiable gambler who turns to fraud as the losses pile up.

Ippei Mizuhara, 39, the former long-time translator and Ohtani's right-hand man, was charged on Thursday with stealing more than $16 million from the Los Angeles Dodgers superstar's bank account in order to pay off gambling debts.

A federal complaint released as the charges against Mizuhara were announced in Los Angeles detailed a jaw-dropping volume of bets over a three-year period -- around 19,000 wagers in total -- at an average value of $12,800 per bet.

Mizuhara's total losses for the period between December 2021 and January 2024 totaled around $40.7 million, according to the complaint.

Text message exchanges between Mizuhara and his bookmakers show the interpreter struggling to keep his head above water as the debts spiral out of control.

In several text messages, Mizuhara requests one last "bump", or increase in credit, from his gambling associates.

"I'm terrible at this sport betting thing huh? Lol . . . Any chance u can bump me again?? As you know, you don't have to worry about me not paying!!" Mizuhara writes in November 2022 to a man identified as "Bookmaker 1" in the complaint.

The following month, Mizuhara again requests a credit increase.

"Can u bump me last 200? I swear on my mom this will be the last ask before I pay it off once I get back to the States," he writes.

In May 2023, "Bookmaker 1" appears to be sympathetic to Mizuhara's unlucky streak, while attempting to verify that the interpreter will soon be in a position to pay off his debts.

"I know you've been on a bad run," the bookmaker writes. "I don't mind bumping u, I just want to verify that you can send at least 2M ($2 million) on June 1."

But later in June, Mizuhara is back requesting another increase.

"I got my ass kicked again lol . . . . Any chance I can get one last bump? This will be my last one for a while if I lose it," he writes.

By November however, it is clear that Mizuhara's bookmaker is losing patience.

In one message the bookmaker appears to indicate that he is watching Ohtani walk his dog near his home in Newport Beach, California.

"Hey Ippie, it's 2 o'clock on Friday. I don't know why you're not returning my calls," the bookmaker writes. "I'm here in Newport Beach and I see (Ohtani) walking his dog. I'm just gonna go up and talk to him and ask how I can get in touch with you since you're not responding? Please call me back immediately."

In January this year, the bookmaker warns Mizuhara that the interpreter is risking a situation "where this is going to get out of control."

"If I don't hear from you by the end of the day today it's gonna [sic] be out of my hands," the bookmaker writes in a message.

Mizuhara responds later that day, admitting: "To be honest with you, I'm really struggling right now and I need some time before I start to make payments."

In March, Mizuhara messages the bookmaker asking if he has seen media reports in which Ohtani states that he has been been the victim of a massive theft by his translator.

"Yes, but that's all bullshit," the bookmaker replies. "Obviously you didn't steal from him."

Mizuhara however replies with an apparent admission of guilt.

"Technically I did steal from him," he writes. "It's all over for me."