A federal prosecutor told jurors in Michael Avenatti's extortion case Wednesday that the embattled celebrity lawyer had "sold out" his own client when he demanded that Nike Inc. pay him millions of dollars to keep quiet about allegedly illicit payments the company made to the families of college basketball recruits.

Assistant U.S. Attorney Robert Sobelman said in his opening statement that Avenatti, known for his representation of adult film star Stormy Daniels in her lawsuit against President Donald Trump, had used claims by youth basketball coach Gary Franklin to "line his own pockets," rather than secure justice for his client.

The prosecutor said Avenatti used his large social media following and nearly ubiquitous media presence as a "modern weapon" to force Nike to pay him as much as $25 million to head an internal investigation of Nike's recruiting practices. The government has alleged that Avenatti did not tell Franklin about earlier offers from the company to settle Franklin's claims without paying Avenatti and fellow attorney Mark Geragos to spearhead the probe.

"When the defendant looked at the coach, he didn't see a client to help. He saw dollar signs," Sobelman told a jury of six men and six women Wednesday afternoon in Manhattan courtroom.

"The defendant had not just crossed the line, he had leaped over it with a running start," he said.

The statements came as attorneys on both sides laid out their arguments at the beginning of an anticipated two-and-a-half-week trial in the U.S. District Court for the Southern District of New York.

Avenatti has pleaded not guilty to charges of extortion and honest services fraud stemming from his dealings last March with Nike and its attorneys, which were recorded by federal law enforcement agents.

Defense attorney Howard Srebnick on Wednesday described Avenatti as a "tenacious" and "sometimes outrageous" lawyer whose outsize public persona made him the perfect advocate to take on the sports apparel giant.

Avenatti's negotiations, he said, were "not extortion," but rather zealous advocacy on behalf of Franklin, who had said he felt "strong-armed" by Nike, when the company pulled its $72,000 sponsorship of his California basketball league.

According to Srebnick, Franklin and an adviser came to Avenatti for restitution and to expose widespread corruption at the firm.

"It's not extortion because you use harsh language in the course of negotiations for your client," Srebnick said.

Nike has not been charged in connection with any alleged recruiting violations, and has denied wrongdoing.

Sobelman cautioned the jury that "Nike was not on trial," and said the prosecution would present evidence of Avenatti's debts at the time to show the case was all about money.

"This trial is about how Franklin was victimized by the defendant, his own lawyer," Sobelman said, adding that Avenatti had "used Franklin to make millions for himself."

Avenatti's lawyers, however, have made it clear that they intend to put Nike under a microscope and potentially call employees at the firm to testify at trial. Srebnick said Avenatti was trying to achieve dual goals of securing a settlement for Franklin, as well as preventing a "whitewashing" of his client's claims.

"That's not extortion. That's not fraud," Srebnick said. "That's litigation. That's exactly what it was."

"This courtroom," he told the jury, "will be a fight for credibility. It will be a search for the truth by you."

Avenatti, meanwhile, will wait out the trial from a jail cell in the special housing unit of the Metropolitan Correctional Center, after a federal judge in California revoked his bail in California, where he was accused in a sprawling indictment of defrauding his former clients.

He also faces a planned trial in New York on charges that he skimmed money from a book deal that was being paid to Daniels, whose real name is Stephanie Clifford.

Avenatti has denied all charges, claiming that his outspoken stances against Trump had made him a target of the president and his Justice Department.

Prosecutors had asked U.S. District Judge Paul Gardephe to keep any references to Trump and Daniels out of the extortion trial, but the judge denied the request as impractical, given Avenatti's notoriety in the press.

Gardephe did, however, allow the prosecutors to tell the jury about some $11 million in debt Avenatti had at the time he first contacted Nike last March.

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