Chauncey Billups pleaded not guilty in a federal courthouse in Brooklyn on Monday, a month after he was arrested for allegedly helping the mafia rig underground poker games, a scandal that rocked the NBA.

The now-suspended Portland Trailblazers head coach was arraigned on charges relating to wire fraud and money laundering, appearing alongside 30 other defendants in the Eastern District of New York.

According to the feds, defendants, including members from four of the five crime families in NYC, would lure unsuspecting wealthy targets to card games under the guise they were legit ... using celebrities like Billups to make them appear legit.

But, officials say they were anything but above board. Legal docs say organizers would use everything from X-ray tables, special contact lenses,

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