An 18-year-old baseball fan has filed a legal claim that he is the rightful owner of Shohei Ohtani's 50-50 home-run ball after it was put up for auction.

Los Angeles Dodgers superstar Ohtani made baseball history last Thursday by becoming the first player to hit 50 home runs and steal 50 bases in a season.

The 30-year-old reached the milestone during the seventh innings of the Dodgers' 20-4 win at the Miami Marlins.

The following day, Goldin auction house was contacted by an anonymous fan and subsequently listed the ball, with a starting bid of $500,000 (£375,000) and an option to purchase it privately for $4.5m (£3.4m).

But Max Matus said in a legal claim filed on Wednesday in Florida's 11th Judicial Circuit Court that he grabbed the ball for Ohtani's 50th homer and another fan wrested it from his hand.

Matus says the ball was briefly in his possession before a man identified as Chris Belanski "wrapped his legs around Max's arm and used his hands to wrangle the ball out of Max's hand, stealing the ball for himself".

The claim names the auction house, Belanski and Kelvin Ramirez, who attended the game with Belanski, as defendants in the case.

The filing includes photos taken by other fans that Matus says support his claim, including one that shows Belanski showing off the ball in front of a stunned Matus.

Goldin told ESPN that it would proceed with the auction after reviewing Matus' claims.

"Max has suffered irreparable harm because of the nature of the unique, irreplaceable 50-50 ball," the legal claim reads. "There is no adequate remedy at law that can replace this unique and extraordinary 50-50 ball."

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