Shohei Ohtani's interpreter was fired by the Los Angeles Dodgers on Thursday after the Japanese baseball star's representatives alleged he had been the victim of "a massive theft" reported to involve millions of dollars.

Ippei Mizuhara, who is also a close friend of Ohtani and often seen with him, is said to have stolen money from the player to place bets with a suspected illegal bookmaker.

"The team can confirm that interpreter Ippei Mizuhara has been terminated," a Dodgers spokesperson said in an email to AFP.

The Dodgers are in Seoul for a season-opening series against the San Diego Padres.

"Shohei's ready," he said. "I know that he's preparing. He's in a hitter's meeting right now and he's going to be ready for tonight's game."

Roberts said the possibility of Ohtani missing the game was "not considered."

He refused to comment on reports that Mizuhara addressed the team after their Game 1 win over the Padres on Wednesday, and could not confirm the interpreter's current whereabouts.

Mizuhara was seen in the dugout during the game talking to Ohtani.

The Los Angeles Times reported that West Hollywood law firm Berk Brettler LLP had looked into Mizuhara's actions after the newspaper learned that Ohtani's name had surfaced in a federal investigation of alleged illegal bookmaker Mathew Bowyer.

"In the course of responding to recent media inquiries, we discovered that Shohei has been the victim of a massive theft and we are turning the matter over to the authorities," Berk Brettler said in a statement.

The LA Times, citing two anonymous sources, said the money involved "was in the millions of dollars" and Mizuhara allegedly used it to place bets with Bowyer's operation.

ESPN reported questions had arisen around "at least $4.5 million in wire transfers sent from Ohtani's bank account" to an associate of Bowyer.

ESPN said that multiple sources, including Mizuhara himself, told ESPN that Ohtani doesn't gamble and that the funds covered Mizuhara's losses.

Major League Baseball's gambling policy bars "any player, umpire, or club or league official or employee" from betting on baseball or making illegal bets on any other sport.

While sports betting has been legalized in a majority of U.S. states, online betting and retail sports books remain illegal in California.