Boxer Floyd Mayweather Jr's nickname is 'Money,' but he doesn't seem to be that worried about losing it.

The unbeaten WBC welterweight champion is an avid sports gambler known for posting (legal) winning bet tickets to Instagram and Twitter. On the 'Jim Rome on Showtime' show Wednesday night, Rome asked Mayweather about his biggest winning bet, which the boxer claimed was between $1.1 - $1.2 million. Rome then asked about Mayweather's biggest losing bet, which the champ estimated to be $1 million. Mayweather said that the disputed last-second, 'Hail Mary' touchdown in last season's Seahawks win over the Packers cost him dearly.

“I lost when Green Bay … Seattle Seahawks threw the pass at the end. I lost 900 grand,” said Mayweather.

That's nearly a million dollar-loss on one play botched by replacement referees. Yikes!

While $900,000 seems like a lot of money — only because it is — to Mayweather, who made $85 million as the highest paid athlete in sports in 2012, it's a little over 1 percent of his annual earnings. Think about that next time you shell out cash to watch one of Mayweather's fights. That money he's gambling with is partially yours.

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