Floyd Mayweather Jr. has reported earnings of roughly $1 billion over the span of his legendary boxing career, but he claims to haven't always done the best job at keeping on top of his fortune along the way.

TMZ Sports reported Friday that the retired, undefeated boxing icon is suing his ex-girlfriend, Shantel Jackson, alleging that she sneakily used his credit cards to lure some of his cash.

According to the lawsuit, as reported by TMZ, Mayweather claims Jackson got access to his credit cards and took liberty to snag cash in his house to go on shopping sprees. He also alleges that she shipped his cash to a secret location, all while showering him with public praises to build up his confidence in their then-relationship.

"As a result of that confidence, Mayweather, who's education ended at eighth grade, did not audit or otherwise inspect either his cash or his credit card statements for theft by Jackson," Mayweather's attorney wrote in the court documents, as reported by TMZ Sports.

Mayweather's reps later told TMZ that the boxing great actually left school in the 12th grade, with his lawsuit adding that he got privy to Jackson's alleged activity when their mutual friend told him that she had been boasting about her money moves at his expense.

These exes aren't any stranger to one another when it comes to court, with Jackson's lawsuits against Mayweather, 40, for domestic abuse and invasion of privacy still active, as reported by TMZ.

This story follows a different TMZ Sports report about Mayweather's Beverly Hills mansion being robbed earlier this week.

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