After sacking countless quarterbacks during his illustrious 13-year NFL career, Dwight Freeney is looking to take down another, more formidable opponent.

The seven-time Pro Bowler, who is a free agent after playing the last two seasons with the San Diego Chargers, recently filed a $20 million lawsuit against Bank of America Merrill Lynch. Freeney claims he was the "target of an elaborate fraud scheme 'aided and abetted' by" Bank of America.

Five years ago Freeney hired the financial institution to manage his money. At that time Freeney was in the middle of a six-year, $72 million contract that made him the highest paid defensive player in NFL history.

Freeney's advisor at Bank of America was Eva Weinberg, who was working with a colleague named Michael Bock. The pair brought in a third man named Michael Stern, who was Weinberg's romantic partner. Freeney says Stern was introduced to him under a fake name, Michael Millar.

Weinberg left Bank of America in June 2010 without notifying Freeney. Nobody at the bank notified him either. Thus he remained Weinberg's client, and Freeney claims shortly thereafter Weinberg and Stern stole $9 million from his accounts. That Weinberg and Stern swindled Freeney is not under question; in 2013 they were both sentenced to five years in prison and ordered to pay Freeney a combined $4.7 million.

Freeney's attorney, Jeffrey Isaacs, told Fortune reporter Daniel Roberts, that Bank of America hasn't shouldered enough of the blame for the crimes of Weinberg and Stern.

The bank itself is arguing that Weinberg wasn't associated with the institution at the time and that Stern was never an employee.

“Although we sympathize with Mr. Freeney as the victim of a crime, the bank had nothing to do with the criminal scheme,” a bank spokesperson told Fortune. “If a client at Merrill Lynch is wronged by Merrill Lynch, we make good on that, and frankly, it is not a long process. But we do not take on responsibility for a former employee’s actions when they’re no longer with the bank.”

Michael Bock, who worked with Weinberg at Bank of America, is still employed there. But the bank says there's no evidence that he was involved in any scheme to steal from Freeney.

The ordeal has been particularly devastating to Freeney because he was in the midst of operating a restaurant in Los Angeles. Freeney, now 35 years old, had partnered with Rolling Stone magazine on the venture, but since losing the money he says they've backed off.

"Obviously we know restaurants are very risky investments, so it was already uphill," Freeney told Fortune, "But when you have a bank stealing from you, you have no chance. I did small things here and there over the years, but this was my first really big business deal. And I wanted to get professional people behind me who knew what they were doing."

Freeney told Fortune people are scolding him for not being careful enough with his money, but he says it was a tricky situation.

"They’re supposed to be protecting me," Freeney said. "And if the people protecting you are the ones stealing from you, what are you supposed to do? They’re supposed to be the ones who keep the bad people away. Instead they had people just running rampant."

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