Ippei Mizuhara, the former interpreter for Dodgers superstar Shohei Ohtani, is said to be negotiating a guilty plea with federal investigators, according to a report from The New York Times. 

The investigation, which began about three weeks ago after attorneys for Ohtani claimed that Mizuhara had engaged in "massive theft" of Ohtani's money to cover sports gambling debts with an illegal bookmaker, is a collaborative effort between the United States Attorney's Office for the Central District of California, the Internal Revenue Service's criminal division and the Department of Homeland Security, the Times said. 

They say that the investigation is "rapidly nearing a conclusion."

"Those briefed on the matter claim that prosecutors have uncovered evidence that Mizuhara may have stolen more money from Ohtani than the $4.5 million he was initially accused of pilfering," said NYT's report, which cites three people who have been briefed on the situation. "In particular, the authorities think they have evidence that Mizuhara was able to change the settings on Ohtani's bank account so Ohtani would not receive alerts and confirmations about transactions, the three people said."

They say that by his quickly pleading guilty, he faces heightened odds of a less severe sentence. 

Michael Freedman, the attorney representing Mizuhara, said that they have no comment on the matter when reached by CBS News. 

Related: MLB launches investigation into gambling allegations surrounding Shohei Ohtani and his former interpreter

Mizuhara was fired in March after news of the allegations made headlines while the team was in South Korea for the Seoul Series, which opened MLB's season. 

Before they fired him, he addressed the entire Dodgers team in the locker room following their first game to speak on his gambling addiction and that Ohtani had what he owed.

The Times says that Ohtani, who is not fluent in English, did not fully understand the message at the time, but was able to pick up on the gist of the conversation. He confronted Mizuhara once they arrived at the team hotel, at which point he learned that the money was stolen from him. 

Mizuhara has previously told ESPN's Tisha Thompson that Ohtani was aware of the debt, and that while disappointed, he would pay them off. That story quickly changed before the Worldwide Leader in Sports was able to publish the piece, with Mizuhara instead saying that Ohtani had no knowledge of the situation and was not responsible for the money transfers to the bookmaker. 

"Initially, a spokesman for Ohtani told ESPN the slugger had transferred the funds to cover Mizuhara's gambling debt. The spokesman presented Mizuhara to ESPN for a 90-minute interview Tuesday night, during which Mizuhara laid out his account in great detail," Thompson wrote. "However, as ESPN prepared to publish the story Wednesday, the spokesman disavowed Mizuhara's account and said Ohtani's lawyers would issue a statement."

In a press conference days after the allegations came to light, Ohtani claimed that he has never bet on baseball or any other sport. 

"I do want to make it clear I never bet on sports or have willfully sent money to the bookmaker," Ohtani said through his new translator, Will Ireton while speaking to press. "To summarize how I'm feeling right now, I'm beyond shocked. It's hard to verbalize how I'm feeling at this point."

Mizuhara had worked with Ohtani since 2018, when he first joined the Los Angeles Angels after being posted by the Hokkaido Nippon-Ham Fighters of the Nippon Professional Baseball League. 

Ohtani signed a massive 10-year, $700 million deal with the Dodgers following the 2023 season. Mizuhara followed the star two-way player from Anaheim to LA where he was to continue as his interpreter. 

The duo's relationship was widely covered by sports media during their time with the Halos, where they were fan favorites for their light-hearted friendship. 

On top of the theft allegations, some questions about Mizuhara's background have recently come to light. 

An Angels media guide previously stated that he graduated from UC Riverside, but the school publicly announced that they had no records of anyone with the same name ever having attended the school. Similarly, Mizuhara was believed to have worked for the Boston Red Sox as an interpreter for one of their former players, but the team issued a statement to disclose that he was "never employed by the Boston Red Sox in any capacity and was not an interpreter."

The current investigation is said to be linked with a larger and ongoing probe into Matthew Bowyer. He is under federal investigation in a case that includes former Dodger Yasiel Puig, who faces multiple charges.

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